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PROBATIONARY OFFICER

COMPUTER KNOWLEDGE NOTES..............................................................................

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AN INTRODUCTION TO COMPUTERTECHNOLOGYThis lesson introduces key concepts related to howcomputers work. Computerrelatedterms are defined and basic computer functions areexplained. In particular,the following topics are addressed.What is a computer?What are the components of a computer?How does a computer work?How does the software work?How does a computer process information?How does the computer’s memory work?How is data stored?Why is documentation important?What are viruses?

WHAT IS A COMPUTER?A computer allows users to store and processinformation quickly and automatically.A computer is a programmable machine. It allows theuser to store all sorts of information and then ‘process’that information, or data, or carry out actions with theinformation, such as calculating numbers or organisingwords.Computer: A machine that can receive and storeinformation and change or process it.Information: Knowledge that is communicated.Data (pl.): The representation of information in aformalised manner suitable for communication,interpretation and processing, generally by a computersystem. Note: the term ‘raw data’ refers tounprocessed information.Computers can be generally classified by size andpower, although there can be considerable overlap.

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Following are descriptions of several different types ofcomputers.Mainframe computers are large-sized, powerfulmulti-user computers that can support concurrentprograms. That means, they can perform differentactions or ‘processes’ at the same time. Mainframecomputers can be used by as many as hundreds orthousands of users at the same time. Largeorganisations may use a mainframe computer toexecute large-scale processes such as processing theorganisation’s payroll.Mini-computers are mid-sized multi-processingcomputers. Again, they can performseveral actions at the same time and can support from4 to 200 users simultaneously.In recent years the distinction between mini-computersand small mainframes has become blurred. Often thedistinction depends upon how the manufacturer wantsto market its machines. Organisations may use a mini-computer for such tasks as managing the informationin a small financial system or maintaining a smalldatabase of information about registrations orapplications

Workstations are powerful, single-user computers.They have the capacity to store and process largequantities of data, but they are only used by oneperson at a time.However, workstations are typically linked together toform a computer network called a local area network,which means that several people, such as staff in anoffice, can communicate with each other and shareelectronic files and data.Computer network: A grouping of computers andperipherals connected together by telecommunications

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links to enable a group of users to share and exchangeinformation.Personal computers (PCs), also calledmicrocomputers, are the most popular type ofcomputer in use today. The PC is a small-sized,relatively inexpensive computer designed for anindividual user. Today, the world of PCs is basicallydivided between IBM-compatible and Macintosh-compatible machines, named after the two computermanufacturers. Computers may be called ‘desktop’computers, which stay on the desk, or ‘laptop’computers, which are lightweight and portable.Organisations and individuals use PCs for a wide rangeof tasks, including word processing, accounting,desktop publishing, preparation and delivery ofpresentations, organisation of spreadsheets anddatabase management. Entry-level PCs are much morepowerful than a few years ago, and today there is littledistinction between PCs and workstations.Personal computers (PCs), also calledmicrocomputers, are the most popular type ofcomputer in use today. The PC is a small-sized,relatively inexpensive computer designed for anindividual user. Today, the world of PCs is basicallydivided betweenIBM-compatible and Macintosh-compatible machines,named after the two computer manufacturers.Computers may be called ‘desktop’ computers, whichstay on the desk, or ‘laptop’ computers, which arelightweight and portable. Organisations andindividuals use PCs for a wide range of tasks, includingword processing, accounting, desktop publishing,preparation and delivery of presentations, organisationof spreadsheets and database management.

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Entry-level PCs are much more powerful than a fewyears ago, and today there is little distinction betweenPCs and workstations.

WHAT ARE THE COMPONENTS OF A COMPUTER?Computers are made up of two parts: the hardwareand the software.Hardware: The physical equipment required to create,use, manipulate and store electronic data.Software: The computerised instructions that operatea computer, manipulate the data and execute particularfunctions or tasks.All computers require the following hardwarecomponents:central processing unit (CPU)Central processing unit (CPU): The chip or chips atthe heart of a computer that enable it to process data.Also known as a processor.memoryMemory: An area within a computer system that holdsdata waiting to be processed.storage deviceStorage device: The place where a computer putsdata.input devices : the devices that allow data andinstructions to enter a computer(such as a keyboard, mouse, scanner)Input: Any resource required for the functioning of aprocess, in the course of which it will be transformedinto one or more outputs.output devices: the devices that allow informationto be represented (that is,given out) to the user, such as a display screen orprinter)

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Output: The product of the transformation of inputs bya process. Printers, scanners and external disk drivesthat may be connected to the computer arealso sometimes called ‘peripheral devices’.Peripheral device: Any piece of equipment in acomputer system that is not actually inside thecomputer itself.The central processing unit (CPU) is the heart of thecomputer. It carries out all of the instructions given ina program, such as a word processing or spreadsheetprogram.The CPU consists of one or more chips (another namefor “integrated circuits”).Chip: A small piece of semi-conducting material (suchas silicon) about 1 centimetre (¼ inch) square onwhich an integrated circuit is embedded. An integratedcircuit is a number of electronic components joinedtogether to form a path for electricity. Centralprocessing unit chips contain the circuits representingthe CPU.A microprocessor is a particular type of chip. Theoriginal IBM personal computer used the Intel 8088microprocessor. Most of today’s microcomputers aredesigned around a microprocessor from one of twoproduct families: x86 or Power. The 80286, 80386, and80486 models that followed were referred to by thelast three digits, 286,386, and 486. For the nextgeneration, however, Intel broke with tradition andintroduced the Pentium in 1993. In 1997, it introducedthe Pentium II to address multi-media applications, andmost recently the Pentium III to address the newopportunities provided by access to large volumes ofinformation on the world wide Web. Othermanufacturers of chips (such as Cyrix) produce chips ofsimilar power and capabilities.

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CPU’s are not all equal. Some process data faster thanothers. A computer contains a system clock that emitspulses to establish the timing of all systems operations.The system clock operates at a speed quite differentfrom a clock that keeps track of the time of the day.The system clock determines the speed at which thecomputer can execute an instruction, and thereforelimits the number of instructions the computercan complete within a specific amount of time. Thetime to complete an instruction execution cycle ismeasured in megahertz (MHz) or millions of cycles persecond.Although some instructions require multiple cycles tocomplete, the processor speed should be thought of interms of the number of instructions the processor canexecute in one second. Today, microprocessor speedsexceed 300 MHz. If all other specifications are identical,then higher megahertz ratings means fasterprocessing.When determining what type of computer you areusing or considering what type of computer to acquire,it is important to know that these terms – 286, 386,486, Pentium– refer to the type of processor in the computer. Newercomputers will come with Pentium microprocessors (orthe equivalent from other manufacturers); older oneswith microprocessors from the x86 family.It is important to know the type of processor in yourcomputer. Some newer computer programs will not runon older processors, and some newer processors aretoo sophisticated for older software.The faster the processor in a computer, the morequickly the computer will perform operations.The most common type of memory that most users arefamiliar with is ‘main memory’

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or ‘RAM’ (random-access memory).Random access memory (RAM): An area in thecomputer system unit that temporarily holds a user’sdata, operating system instructions and programinstructions.The word ‘main’ is used to distinguish it from externalmass storage devices such as the hard drive or diskdrives. Note that the term ‘mass storage’ refers tovarious techniques and devices for storing largeamounts of data; mass storage is distinct from memorybecause it retains data even when the computer isturned off. Thus mass storage is sometimes referred toas ‘auxiliary storage’. Following are definitions ofcommon storage devices:Storage: The area within a computer system wheredata can be left on a longer term basis while it is notneeded for processing.Diskette. A small, removable, flexible mylar plasticdisk covered with a thin layer of a magnetisablesubstance, onto which digital data can be recorded andstored. Also known as a floppy disk.Hard drive: The storage area within the computeritself, where megabytes of space are available to storebits of information. Also known as a hard disk.Optical disk: A storage device that uses reflectingsurfaces and laser technology to read and write data ona disk. Also known as a laser disk.Magnetic tape: A continuous plastic strip covered withmagnetic oxide; the tape is divided into parallel tracksonto which data may be recorded by selectivelymagnetising parts of the surface, or spots, in each ofthe tracks. The data can then be stored and reused

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HOW DOES A COMPUTER WORK?A computer functions in the following manner:The computer accepts input. Computer input iswhatever is entered or fed into a computer system.Input can be supplied by a person (such as by using akeyboard) or by another computer or device (such as adiskette or CD-ROM). Some examples of input includethe words and symbols in a document, numbers for acalculation, instructions for completing a process,pictures, and so on.The computer performs useful operations,manipulating the data in many ways.This manipulation is called processing. Examples ofprocessing include performing calculations, sorting listsof words or numbers, modifying documentsand pictures according to user instructions, anddrawing graphs. A computerprocesses data in the CPU.Process: A systematic series of actions a computeruses to manipulate data.The computer stores data. A computer muststore data so that it is available for processing. Mostcomputers have more than one location for storingdata (the hard drive or C:\, and the floppy drive orA:\). The place where the computer stores the datadepends on how the data is being used. The computerputs the data in one place while it is waiting to beprocessed and another place when it is not needed forimmediate processing. The storage of data in thecomputer is called ‘online storage’ while the storage ofdata on computer tapes, diskettes or CD-ROMs is called‘offline storage’

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The computer produces output. Computeroutput is information that has been produced by acomputer. Some examples of computer output includereports,documents, music, graphs, and pictures.Output can be in several different formats, such aspaper, diskette, or on screen.A computer receives data as input, processes it, storesit and then produces output.

HOW DOES THE SOFTWARE WORK?Software is the computerised instructions that operatethe computer, execute particular functions or tasks,and manipulate the data. For software (theinstructions) to perform various functions, it must beprogrammed. That is, the instructions need to bewritten in a programming language that the computercan understand. Without a program, a computer isuseless.Programming language: An artificial set of rules,vocabulary and syntax used to instruct the computer toexecute certain tasks.Computer program: A sequence of instructions thatcan be executed by a computer to carry out a process.Over the years, a wide range of programminglanguages have been developed,including BASIC, FORTRAN, PASCAL, C++, JAVA, andso on. Each language has a unique set of words (codes)that it understands and a special syntax for organisingprogram instructions.The language the computer actually understands iscalled machine language, which comprises numbersonly. This language is used by the computer tounderstand the programming language and translatethe terms into executable instructions. Lying between

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programming languages and machine languages areassembly languages.Assembly languages have the same structure and setof commands as machine languages but they enable aprogram to use names instead of numbers.Please note: most people who use computers today donot need to worry about programming, machine, orassembly languages. This is because the softwarebeing used today is written in a highly user-friendlymanner and in a way that does not require knowledgeof the computer languages which were used to createand use it.User friendly: Computer software or hardware that issimple to set up, run and use.There are two kinds of software, systems software andapplications software.Systems software includes the operating system andall the utilities that enable the computer to function.The most important program that runs on a computeris the operating system. Every general-purposecomputer must have an operating system in order torun other programs. This includes controlling functionssuch as the coordination of the hardware andapplications software, allocating storage facilities,controlling the input and output devices and managingtime sharing for linked or networked computers. Inmany respects an operating system works like an airtraffic controller to coordinate activities within thecomputer. Examples of operating systems are WindowsNT, DOS and OS/2. The Windows family of operatingsystems includes a Graphical User Interface (GUI) thatmakes the software user friendly.Operating system: A collection of software thatallows a computer to function.

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Applications software includes programs that usersaccess to carry out work. They include applications forthe following functions.Word processing is the most common applicationssoftware. The great advantage of word processing overusing a typewriter is that you can make changeswithout retyping the entire document. Word processorsmake it easy to manipulate and format documents.Spreadsheets are computer programs that letpeople electronically create and manipulatespreadsheets (tables of values arranged in rows andcolumns with predefined relationships to each other).Spreadsheets are used for mathematical calculationssuch as accounts, budgets, statistics and so on.Database management applications are computerprograms that let people create and manipulate data ina database. A database is a collection of relatedinformation that can be manipulated and used to sortinformation, conduct statistical analyses or generatereports.Presentation packages and graphics are computerprograms that enable users to create highly stylisedimages for slide presentations and reports. They canalso be used to produce various types of charts andgraphs. Many software applications include graphicscomponents including: paint programs, desktoppublishing applications and so on.Communications applications typically includesoftware to enable people to send faxes and emails anddial into other computers.Software programs are continually being written orupgraded to undertake certain tasks. As a result thesoftware can become obsolete quickly.

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Software can be either ‘proprietary’ (also called‘closed’) or ‘open’. Proprietary software is privatelyowned and controlled. A proprietary software design ortechnique is one that is owned by a company, whichwill usually not divulge specifications that would allowother companies to duplicate the product.Increasingly, proprietary software is seen as adisadvantage in many organisations; users prefer touse ‘open’ software, which is software designed usingspecifications that are publicly accessible. The greatadvantage of open software is that anyone can createadd-on products for it because they can understandhow it was designed.

HOW DOES A COMPUTER PROCESSINFORMATION?

When data is input into a computer, the numbers orwords we understand are translated into a binarynumbers system. Binary is the language of computers.Everything you type, input, output, send, retrieve,draw and so on is, in the end, converted to thecomputer’s native language: binary.Binary number system: A numerical system whereineach digit stands for a power of two. The binary systemuses only two symbols, 0 and 1, to represent values.In the decimal system, commonly used in mostcountries, each digit represents a valueof 10. For example, the number 103 would break downas follows:1 x 100 = 1000 x 10 = 03 x 1 = 3103 = 103

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In the binary system, each digit position represents avalue of 2. Because computers use the binary system,powers of 2 play an important role. This is whyeverything in computers seems to come in 8s (2 to the3rd power), 64s (2 to the 6th power), 128s (2to the 7th power), and 256s (2 to the 8th power).Therefore, in the binary system, the number 103 wouldbreak down as follows:1 x 64 = 641 x 32 = 320 x 16 = 00 x 8 = 01 x 4 = 41 x 2 = 21 x 1 = 11100111 = 103The values in a binary system -- the 0s and 1s -- arecalled ‘binary digits’ or bits.Binary digit (bit): A digit within the binary numbersystem. A bit is the smallest unit of information held ina computer.The computer’s electronic circuits have only two states,on or off, and therefore can only understand 0s and 1s,which may represent such opposites as on or off, yesor no, or up or down. This is why all computers use thebinary system. In order to make the bits useful, theyare combined into ‘bytes’ of information.Byte: A combination of bits that represent onecharacter. A byte is usually composed of 8 bitsComputer programmers have developed codes forvarious bytes of information, so that they may be readby different computer programs. For example, onecode might define the letter A as ‘11000001’ and theletter B as 11000010’.

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The number 6 might be defined as ‘11110110’ and thenumber 8 as ‘11111000’. When the person enteringdata strikes the A key on the keyboard, the computerregisters it as ‘11000001’. When he or she enters theB, the computer reads it as ‘11000010’. Similarly, thenumber 6 is understood by the computer as ‘11110110’and the number 8 as ‘1111100’. In this way, thecomputer can store words and numbers as binary digitsand then retrieve them and convert them back intowords or numbers as required.As discussed earlier, this work of manipulating, storingand processing the data takes place in the CentralProcessing Unit, the computer’s main memory. TheCPU consists of an arithmetic and logic unit, or ALU, acontrol unit, and a set of registers.The arithmetic and logic unit is the portion of theCPU where arithmetic and logical operations take place.The control unit is the part of the CPU thatsupervises the general operations of the computer.The registers are devices that hold data inside thecomputer’s memory long enough to execute aparticular function, such as indexing, calculating,sorting or otherwise manipulating data. They are theCPU’s own internal memory.Data travels from one part of the computer to anotherthrough a kind of path known as a bus.Bus: The channel or path that lets the parts of acomputer communicate with each other.Similar to a school bus for school children, a computerdata bus picks up a load of data from one of thecomponents on the main computer board and thentransfers the data to another component on the maincomputer board. The main circuit board of amicrocomputer is also known as the motherboard. Themotherboard is the principal board that has connectors

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for attaching devices to the bus. Typically, it containsthe CPU, memory and basic controllers for the system.The data bus is really a series of electrical circuits thatconnect the various electrical elements on the mainboard.The data are input into the computer and processed inthe CPU. They travel along the bus to be stored in thecomputer’s memory. The amount of memory availableis described in bytes of information, referring to thecombination of bits representing characters. The higherthe number of bytes the more memory the computerhas.Today’s computers hold ‘megabytes’ or even‘gigabytes’ of data. A megabyte is a unit of one millionbytes; a gigabyte is one billion bytes, and a terabyte isone trillion bytes. If a computer has a memory of 64megabytes, then it can hold 64 million bytes ofinformation.Data can be stored so that it is readable again onlyusing the software with which it was created, or it canbe stored in other formats, so that it may betransferred or used by other software programs. Thereis a standard character code used to store data sothat it may be used by other software programs; thiscode is called ASCII or American Standard Code forInformation Interchange. The ASCII code assigns aspecific pattern of bits to each character, as describedabove. Another code that may be found, especially inIBM-brand mainframe computers, is EBCDIC, orExtended Binary Coded Decimal Interchange Code. Theimportant point to remember about these codes is thattheir main value is to store information so that it isreadable by other computers. By using ASCII orEBCDIC, it is possible for people to retrieve and use

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someone else’s data using a different type of hardwareor software. The main disadvantage of using ASCII orEBCDIC is that the formatting or other specialqualities of computerised information may be lost.

WHAT IS COMPUTER MEMORY?

As defined earlier, memory refers to the temporaryinternal storage areas within a computer. The termmemory is usually used as shorthand for ‘physicalmemory’, which refers to the actual chips capable ofholding data. Some computers also use ‘virtualmemory’, which expands physical memory onto a harddrive.The main type of memory and the most familiar tousers is random access memory (RAM). RAM is thesame as main memory. A computer can both write datainto RAM and read data from RAM.Every time a user turns on his or her computer, a setof operating instructions is copied from the hard diskinto RAM. These instructions, which help control basiccomputer functions, remain in RAM until the computeris turned off. Most RAM is volatile, which means that itrequires a steady flow of electricity to maintain itscontents. As soon as the power is turned off, whateverdata was in RAM disappears.The contents of RAM are necessary for the computer toprocess data. The results of the processing are kepttemporarily in RAM until they are needed again or untilthey are saved onto the hard disk or other storagedevice.Today the storage capacity of RAM is measured inmegabytes (MB). PCs (microcomputers) typically havebetween 16 and 64 MB of RAM, which means they

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can hold between 16 and 64 million bytes of data (astandard A4 page of text typically holds about 2,000bytes or characters of text).Other types of memory include

ROM (read only memory): unlike RAM, ROM is non-volatile and only permits the user to read data.Computers almost always contain a small amount ofread-only memory that holds instructions for startingup the computer.PROM (programmable read-only memory): a PROMis a memory chip on which you can store a program.Once the PROM has been used, you cannot wipe itclean and use it to store something else. Like ROMs,PROMs are non-volatile.EPROM (erasable programmable read-onlymemory): an EPROM is a special type of PROM that canbe erased by exposing it to ultraviolet light.EEPROM (electrically erasable programmable read-only memory): an EEPROM is a special type of PROMthat can be erased by exposing it to an electricalcharge.Back up: To copy a computer file or collection of filesto a second medium, usually on a diskette or magnetictape, so that the data are safe in case the original fileis damaged or lost. Backups are usually copied tostorage devices that can be removed from thecomputer and kept separately from the original.A tape backup is a copy of the data from a hard disk,stored on magnetic tape and used to recover lost data.A tape backup is relatively inexpensive and can rescuean organisation from the overwhelming task of tryingto reconstruct lost data.

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Backing up electronic data is critical to protecting itfrom loss or damage.For more information on backingup data and protecting information, see AutomatingRecords Services and Emergency Planning for Recordsand Archives Services.The most popular types of tape drives formicrocomputers also use tape cartridges, butthere are several tape specifications and cartridgesizes. A tape cartridge is a removable magnetic tapemodule similar to a sound or video cassette tape.Quarter inch tape, called QIC, is a tape cartridge thatcontains ¼ inch (approximately ½ centimetre) widetape. Depending on tape length, QIC tape capacitiesrange from 340 MB to 2 gigabytes. Digital audio tape,called DAT, was originally an audio recording format,but is now also used for data storage. The 4mm wideDAT tape format storage capacity ranges from 2gigabytes to 12 gigabytes.In addition to magnetic storage, there is also opticalstorage.Optical disk: A storage device that uses reflectingsurfaces and laser technology to read and write data ona disk. Also known as a laser disk.With optical storage, data is burned into the storagemedium using beams of laser light. The burns formpatterns of small pits in the disk surface to representdata. The pits on optical media are permanent, so thedata cannot be changed. Optical media arevery durable, but they do not provide the flexibility ofmagnetic media for changing the data once they arestored.There are three types of optical disks.CD-ROM’s are the most popular type of opticalstorage. CD-ROM stands for Compact Disc Read OnlyMemory. A computer CD-ROM disk, like its audio

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counterpart, contains data that has been stamped onthe disk surface as a series of pits. To read the data ona CD-ROM an optical read head distinguishes thepatterns of pits that represent bytes. CD-ROM disksprovide tremendous storage capacity. CD-ROMs usuallycome with data already written onto them. These daysmost applications software is provided on CD-ROM.It is now possible for computer users to write datato an optical disk. These are known as WORM disks,which stands for ‘Write Once Read Many’. A single CDholds up to 680 megabytes, equivalent to over 300,000pages of text in character format, and these disks arequite durable. These CDs are know as CD re-recordable(CD-R). There are other types of WORM disks, althoughthere is no standard for these.There is a third type of optical disk which can beerased and use to rewrite new information. These aresometimes known as EO (erasable optical) disks andCD-RW (CD rewritable).Magneto-optical disks combine magnetic disk and CD-ROM technologies. Like magnetic media they can readand written to and like floppy disks they areremovable.They can store over 200 MB of data, and speed ofaccess to this data is faster than a floppy but slowerthan a hard drive. There is no universal standard forthese yet.CD-ROMs and magnet-optical disks are very useful forstoring images. These take up much more storagespace than data in character format, such as in word-processed files.THE IMPORTANCE OF DOCUMENTATIONThe computer hardware, software and peripherals willbe accompanied by documentation, which explains howthe various systems or programs operate.

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Documentation: Information needed to develop, useor maintain computer hardware and software and topermit access and retrieval of the data.Although documentation usually comes in the form ofprinted manuals, guide books, it may also come inelectronic form, such as in ‘help screens’ containedwithin the computer software or documentation in datadictionaries and so on. Often, documentation is createdwhen a specific computer application is used. Forexample, if a government office creates a data base ofemployees in order to administer payroll,documentation may be created describing how thedatabase was established, what it is to be used for andwhat data fields have been created. Thisdocumentation can be critical to understanding thedatabase system, particularly if it is being managed inan archival environment long after the creators of thesystem have left.

Documentation should always be retained.

Disposing of documentation can cause problems in thefuture, particularly if you have to reload software fromthe beginning. Documentation can also contain licencesfor the legitimate use of the software. Therefore it iscritical to protect documentation and ensure it isreadily available.

PROTECTING AGAINST VIRUSESVirus: A computer program that is planted in onecomputer and then transferred, hidden in usefulinformation, to one or more other computers with theintention of corrupting or wiping out information in therecipient computer.

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Viruses are extremely common. Many different types ofviruses exist, ranging from ones that prevent you fromopening up word-processed documents through to onesthat destroy the entire contents of a hard drive. Virusescan be caught in several ways, for example byexchanging floppy disks, via electronic mail messagesand through downloading documents from the Web.Networks make it much easier for viruses to movearound. Once a virus gets into an organisation’scomputer system it can spread very quickly. Newviruses appear each week, so it is essential that usershave up-todate anti-virus software to combat thisproblem.If users have software that is unlicenced it could meanthat it is ‘pirate’ or ‘bootleg’ software. This is softwarethat has been illegally copied. Software of this naturesometimes contains viruses that can be extremelydamaging to computers.

COMPUTING ENVIRONMENTSThis lesson examines three computer environments:mainframe computing, networks (such as Intranets),and the Internet. It introduces key concepts related tohow mainframes, networks and the Internet work.Please remember, this lesson is not intended to providea comprehensive explanation of the technical details ofmainframe computing, networks and the Internet.Information is provided in order to introduce you to keyconcepts and provide an overview of these computingenvironments.

MAINFRAME COMPUTINGMainframe computing developed at a time whencomputational power was an expensive and scarceresource. In order to use the expensive computer

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technologies efficiently, organisations had to sharetheir resources. Many of computerisedapplications, such as invoicing, purchasing, payroll,accounting and so on, involved the organisation as awhole.If the original reasons for the mainframe computingmodel were cost and scarcity of resources, the currentreasons for sharing computer power aresecurity: the protection of data from outside orunauthorised accessintegrity: the guarantee that the data is notcorrupted and that repeatability is achievable using thesame applications and datasystem availability: centralised facilities can beoperated by teams in shifts 24 hours a day, maximisingthe investment in IT equipment and allowing largedata processing activities to be carried out efficientlydata sharing: data input or created in one part ofthe organisation becomes available to other partsapplications: many modern applications, such aspersonnel management systems, require access to ashared pool of resources.Today, mainframe computing is no longer an expensiveresource; sharing is still a cost-effective means ofproviding computational power. Recent studies haveshown that on a per-user basis, mainframe computingprovides the least expensive form of computing.A mainframe environment involves not just thehardware. The security, integrity and availability of themainframe system can only be achieved if thecomputer centre is staffed by people with thenecessary skills, operated according to a set ofpractices and managed with the discipline (that is, theprocesses and procedures) that ensures theappropriate levels of security, integrity and availability.

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This is the ‘mainframe environment’.In a mainframeenvironment, many people share access to amainframe computer.A large central processor is kept in a purpose-builtcomputer centre staffed by personnel responsible formaintaining it. Individuals in the organisation accessthe mainframe computer through terminals on theirdesktops in order to share common organisationalresources, such as software programs or electronicdata. As we use the term today, a mainframe isactually identified more by the ‘environment’ in whichthe mainframe is operated. In other words, thephysical environment: the controlled temperature andhumidity and the physical security of having themainframe behind locked doors.Mainframe computers are used as tools to support agiven ‘business’ application such asprocessing applications for licencesprocessing government payroll informationprocessing financial accountsprocessing environmental resource information.In all of these applications, the common denominator isthe work process and the rules for undertaking theprocess. Everyone is undertaking a part of the wholework process and everyone must complete his or herwork in accordance with the procedures required tomake sure the job is done satisfactorily and the dataare complete and consistent.For example, if ten people are responsible formanaging government payroll, each will have aseparate responsibility. They will all have access to thesame database through the mainframe computer, andeach person must complete his or her task adequatelybefore the ‘job’ can be considered complete.

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The automation of a given work process, such asprocessing government payroll information, is oftenviewed as an information system.Information system: The combination of information,technology, processes and people brought together tosupport a given business objective.The mainframe is the data and application repositoryfor most organisations. It is also the hub for mostonline business activities. It is believed thatmainframes still house 90 per cent of the data majororganisations rely on to conduct their business. Despiteclaims that mainframe technology is dying out, sales ofmainframe hardware and software remain steady. Theterm ‘mainframe’ has always had the image of beingsomething large in size. Yet, however big the early‘room-filling’ mainframes were, today’s modernversions are no bigger than the size of a householdrefrigerator. The level of mainframe sophistication hasgrown over the more than thirty years of its evolution;organisations still recognise its advantages in terms ofperformance, reliability and security.

NETWORK COMPUTINGA network computing environment is one in which anorganisation has linked together personal computersthat have been connected into a network.There are a number of types of computer networks.Local area network: A computer network locatedwithin a relatively limited area such as a building,agency or university campus. Also known as a LAN.Wide area network (WAN): A computer network thatcovers a large geographical area.There are an estimated 25 million computers connectedto local area networks world wide. The purpose of

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networking personal computers and even mainframestogether is to permit employees in the organisation tocommunicate with one another as well as othersoutside the organisation, normally through the use ofelectronic messagesaccess information and services supported on theWorld Wide Webshare documents and datasupport various work processes in the organisationbased on the automation of specific tasks.A network environment can range in sophisticationfrom very simple to very complex.Some networks are used to support simple electronicmail communication. In other networks, employeesmay be able to share documents with each other andcarry out the work of their work groups, project teams,etc. by exchanging electronic documentsthrough e-mail. The most sophisticated organisationsmay have automated entire work processes. Forinstance, draft documents such as responses to letterssent to senior officials, are sent through variousapproval levels (such as action officer to manager todirector to senior official) without ever being printedonto paper (except perhaps the final version, whichneeds to be signed by the senior official).A computer network can be simple and limited to asmall number of computers or complex, linking a largenumber of computers.A computer that is not connected to a network isreferred to as a stand-alone computer. When acomputer is physically connected to a local areanetwork, using a cable or other communicationschannel, the computer becomes a workstation on the

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network. Each device on the network includingworkstations, servers, and printers is referred to as anode.Node: A processing location on a network.A workstation normally has all of the usual resourcesfound in the personal computing environment (harddrive, software, data and printer). However, users ofworkstations will also have access to networkresources, which typically include application software,storage space for data files, and printers other thanthose on the local workstation. On a network, thenetwork server typically provides the applicationssoftware and storage space for data files.Network server: A computer that is connected to thenetwork and that ‘serves’ or distributes resources tonetwork users.Networks use different kinds of servers to carry outspecialised functions. For example, a file server is acomputer and storage device dedicated to storing files.File server: A computer that serves or distributesapplication programs and data files to workstationswithin a computer network. The hard drive of the fileserver is shared by the workstations on the network.Any user on the network can store files on the server.Other types of servers include a print server to manageone or more printers and a database server to processdatabase queries.Most network users will need to understand file serversbecause this is where they will store their files on thenetwork. A typical local area network uses a powerfulPC as a file server. However, a minicomputer ormainframe computer can also be a file server. Fileservers fall into three categories; dedicated, non-dedicated and application servers.

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A dedicated file server is devoted only to the task ofdelivering programs and datafiles to workstations. A dedicated file server does notprocess data or run programsfor the workstations. Instead, programs run using thememory and processor of the workstation.In some cases, a network computer performs a dualrole as both file server and workstation. When a non-dedicated file server is used, the computer workstationfunctions like a normal workstation, but otherworkstations can access programs and data files fromthe hard disk of the user’s computer workstation.An application server is a computer that runsapplications software and runs the results of processingto workstations as requested. An application servermakes it possible to use the processing power of boththe server and the workstation. Use of an applicationserver splits processing between the workstation clientand the network server. The method is also referred toas client/server architecture.Some networks include a host computer, usually aminicomputer or mainframe attached with terminals. Aterminal has a keyboard and screen but does not havea local storage device and does no processing on itsown. When a terminal is connected to a host computer,all processing takes place on the host.The software on a local area network typically includesmany of the same applications one might use in apersonal computing environment, such as wordprocessing, spreadsheet, database management and soon. As the use of networks increase, however,organisations have begun to demand software thatfacilitate the flow and sharing of documents. Thissoftware includes groupware and workflow software.

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Groupware: Applications software that supportscollaborative work between a group of users bymanaging schedules, sharing documents andundertaking intragroup communications.Essentially, groupware manages a pool of documentsand allows users to access those documentssimultaneously. A key feature of groupware isdocument version management which maintains allrevisions within a document when more than onegroup member revises a document.Intranet: An internal computer network that belongstoan organisation and is accessible only by thatorganisation’s members.

THE INTERNETThe Internet evolved over the past thirty years from afledging experiment with four computers into a vastinformation network that connects millions ofmicrocomputers, minicomputers and mainframecomputers. As of 1998, the Internet had more than100 million users world wide, and that number isgrowing rapidly. The Internet is decentralised by designand, remarkably, this anarchy by design works well.Internet: A collection of local, regional and nationalcomputer networks that are linked together toexchange data and distribute processing tasks.There are a variety of ways to access the Internet, themost common being through an Internet ServiceProvider (ISP). An ISP is a company that charges anongoing fee for providing Internet access tobusinesses, organisations and individuals. The ISPprovides the user with the necessary communicationssoftware (such as e-mail) and user account. The usersupplies a modem that connects the computer to theuser’s phone line. The user’s computer dials the ISP’s

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computer and establishes a connection over the phoneline. Once connected the ISP routes data between theuser’s computer and the Internet. Most ISPs offer dial-up Internet connections and electronic mail access,along with additional services. Some ISPs offer directaccess to the Internet without the use of proprietarysoftware.The Internet connects millions of people through acollection of computer networks.A connection that uses a phone line to establish atemporary connection to the Internet is referred to asa dial-up connection. When the user’s computer hangsup, the connection is broken. A phone line provides avery narrow pipe for transmitting data.Its typical capacity is only 28.8 thousand bits persecond (bps). Using a phone line, the time to transferthe contents of a 680 megabyte CD-ROM would be over53 hours.More rapid digital data transmission is now availablefrom some telecoms providers in various parts of theworld.The World Wide Web was created in 1990 as an easy-to-use source of information.World Wide Web: A computer network system thatallows users to browse through information availableon computers round the world.The World Wide Web opened the Internet to millions ofpeople interested in finding information. There are overone million Web sites around the world and the numberis growing very quickly. The World Wide Web consistsof documents called Web pages that containinformation on a particular topic. A Web page mightalso contain one or more links that point to other Webpages.

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Link: A reference to another document in anenvironment like the World Wide Web, that users cango to directly by clicking on the on-screen referencewith the computer’s mouse.Links make it easy to follow a thread of relatedinformation, even if the pages are stored on computerslocated in different countries. Every Web page is storedas an HTML (HyperText Markup Language) document.

HyperText Markup Language (HTML): One of themain standards that controls how the World Wide Webworks; it is an SGML document type definition thatdetermines how Web pages are formatted anddisplayed and thus enables information to beexchanged on the World Wide Web.Standardised General Mark-up Language (SGML):A metalanguage that can be applied to documents inorder to maintain their structure and context.An HTML document contains special instructions calledHTML tags that tell a Web browser how to display thetext, graphics, and background of a Web page.Web browsers are used to view Web pages, transferfiles between computers, access commercialinformation services, send e-mail, and interact withother Internet users.Web browser: A software application that enables auser to locate and view pages on a Web site. Alsoknown as a browser.To request a Web page the user either types in the URL(Uniform Resource Locator)address or uses a ‘mouse’ to click on a Web page link.Uniform Resource Locator (URL): The globaladdress of documents and other resources on theWorld Wide Web. URLs can point to executable filesthat can be fetched using FTP (file transfer protocol,

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ftp://) or a Web page that can be retrieved using HTTP(hypertext transfer protocol, http://).After the http://, the next segment of the address isthe server name. The server is the computer andsoftware that make the data available. A Web server,for instance, is a computer that uses Web serversoftware to transmit Web pages over the Internet.Most Web servers have domain names prefixed withWWW. By entering the Web server name, one accessesthe site’s home page.Home page: The main page of a Website. Typically,the home page serves as an index or table of contentsto other documents stored at the site (that is, theaddress).Website: A location on the World Wide Web.A home page is similar to the title page and table ofcontents in a book. It identifies the site and containslinks to other pages at the site. The following is anexample of a home page belonging to the ICA, viewedusing a particular type of browser software calledMicrosoft Explorer.The Web browser is the gateway to commercialinformation services as well as the free sites on theInternet. A commercial information service providesaccess to computer-based information for a fee. In1997, approximately 17 million peoplesubscribed to the top four commercial informationservices: America On-Line, Compuserve, MicrosoftNetwork and Prodigy.

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Figure 1: Sample Home Page

The server sends the data for the Web page over theInternet to the computer. The data includes two things:the information the user wants to view and a set ofinstructions that tells the browser how to display it. Theinstructions include specifications for the colour of thebackground, the size of the text, and the placementof the graphics. Additional instructions tell the browserwhat to do when the user clicks on a link. Thebrowser’s menu and tool bars help users navigate theWeb as they follow the links. The Back and Forwardbuttons trace and retrace the users’ path

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through the links being followed from one Web page toanother. The browser stores and can display a list ofthe pages being visited during each session. Thebrowser can also store a list of favourite sites, oftencalled bookmarks, to permit the user to jump directlyto the site they wish to see instead of having to enterits URL every time.Users can find information on the Web by using asearch engine. There are a number of Web sites thatprovide search facilities, and the Internet ServiceProvider will linksto these sites.Search engine: A program that searches documentsfor specified keywords and returns a list of documentswhere the keywords were found.COMPUTER APPLICATIONSApplications software includes programs that usersaccess to carry out work. This lesson examines twoapplications that may be of particular use to thestudent: databases and electronic mail (‘e-mail’). Itintroduces key concepts related to how databases ande-mail work.Please remember, this lesson is not intended to providea comprehensive explanation of the technical details ofall applications. Other applications would be wordprocessing, spreadsheets and presentations.

DATABASESA database is a collection of information stored on oneor several computers.Database: A structured assembly of logically relateddata designed to meet various applications butmanaged independently of them. More specifically, adatabase is a self-describing collection of integratedrecords.A database is self-describing in that it contains,in addition to the user’s source data, a

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description of its own structure (such as in a datadictionary). It is the data dictionary that make dataindependence possible (for example, the databasemanagement system maps the data fields into recordsand handles other similar transformation).A database is a collection of information stored oncomputers.Data field: A space allocated for a particular item ofinformation. In a database, fields are the smallest unitsof information you can access.A data field contains a single piece of information (firstname, family name, ministry, employee number, salaryand so on). A collection of data fields comprise a recordsuch as, in this example, an employee record.Database record: A complete set of information in adatabase; records are composed of fields, each ofwhich contains one item of information.A collection of records (in this case, employee records)comprises a database. Structured databases typicallystore data that describes a collection of similar entities.‘Salaries and benefits’ is an example of an entity;‘education/training’ is another entity. A n employeedatabase stores data about the employees in anorganisation. A medical database stores data for acollection of patients. An inventory database storesdata for a collection of items stocked in a warehouse.Data structure: A scheme for organising relatedpieces of information. The basic types of structuresinclude: files, lists, arrays, records, trees, tables. Eachof these basic structures has many variations andallows different operations to be performed on thedata.There are three basic database models.Hierarchical databases exhibit a branchingstructure, with information arranged

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into sets and sub-sets; getting to a particular piece ofdata may require goingthrough several vertically ordered files. An example isthe process involved infinding a distant cousin on a family tree.Network databases offer many more directconnections between files, but,similar to hierarchies, the links are predefined and aredifficult to change or adjust.Object-oriented databases link self containedentities (or objects) together.Objects can be text, a picture, a piece of film or anyitem that can be individuallyselected and manipulated. This kind of database isparticularly useful fororganising large amounts of disparate information, butthey are not designed for structured numericalanalysis.The limitations found with these types of databasesexplain why most organisations have turned torelational databases. Relational databases not onlyaccommodate multiple views but allow new links to beforged as needs arise. Relational databasesare powerful because they require few assumptionsabout how data is related or how itwill be extracted from the database. As a result, thesame database can be viewed inmany different ways.Relational database: A database that spreadsinformation across different tables while maintaininglinks between them.A relational database stores facts in tables calledrelations. The only requirement isthat the information must be capable of being laid outin rows and columns (similar to

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a list of names, addresses and phone numbers). Anexample from a university mighthelp to illustrate the concept. In a very simplified viewof a university database, eachfacet of the university’s administration would berepresented by a table containinginformation within the remit of a single department.The admissions office, forinstance, keeps track of students by ID number, nameand major field of study. The personnel office keepsrecords of the department, rank, names, and socialidentity numbers of the teaching staff, and so on. Thefollowing figure shows examples of relational tables.A relational database stores information acrossdifferent tables and connects them with links in thecomputer.Database management software is used to create andmanipulate databases. Data access software is usuallyused to search databases. The data access softwareunderstands the structure and details of the databasewhich means the user simply hasto enter his or her search specifications, using either amenu, a keyword search engine,a query language or a natural language (amongothers).Menu: A collection of onscreen choices given to theuser to help him or her interact with a computersystem.Database menus are similar to those used in mostsoftware. They are typically arranged as a hierarchy sothat after the user makes a choice at the first level ofthe menu, a second series of choices appears.Keyword searching permits access to databasesthrough the use of keywords.

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Keyword search engine: A program that allows auser to search a database by an index entry thatidentifies a specific record or document.Keyword search engines are especially popular forsearching the many documents stored in a free formdatabase such as the World Wide Web. To use akeyword search engine, the user types in a word andthe search engine locates areas in the databasewhere the word or related information can be found.When information in a database needs to be accessedquickly, it is usually stored as a structured database.However, the structure in structured databases cancause a problem for users who might not know theformat for the records in a database. One way to helpusers search structured databases is by providing a‘query by example’user interface based on the use of a query language.Query language: A set of command words that can beused to direct a computer to create databases, locateinformation, sort records and change the data in thoserecords.One query language is called SQL (structured querylanguage). The use of query language is based onknowledge of the command word and the grammar orsyntax that will let one construct valid query sentences.For example, the SQL command wordfor finding records is SELECT. WHERE is used to specifythat only certain rows of the table are displayed. Forexample, SELECT employee ID no from employeestatistics table WHERE position = ‘Manager’.In more sophisticated systems, queries can also beformulated in a natural language such as standardEnglish, French, or Japanese. In order to use thenatural language, the user is not required to learn aquery language. Queries can be straightforward such

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as: ‘What records of World War Two are available inthe archival institution’? This form of searching is stillunder development although examples of its use arespreading rapidly.Users can ask questions of the database using a varietyof query languages, which formulate questions so thatthe computer can perform operations and provideresults.

COMMUNICATING BY COMPUTER

Communicating via e-mail is rapidly becoming asimportant as telephone and fax communication andforms an important component of any officeautomation system.Electronic mail (e-mail): A way of sending messagesbetween people anywhere within an organisation or inthe world using a computer that can communicate withanother computer through a computer network. Themessage or document can be viewed on a computerscreen and printed out.E-mail is handled by a variety of software programssuch as Microsoft Outlook Express, Eudora, elm, pineand so on. The message originator creates a messagefile in the e-mail software editor. When complete, themessage is posted to a message transport system thatassumes the responsibility for delivering that messageto its recipient(s) ‘mailbox’.To receive and read the message, the recipient runs asoftware program that retrieves incoming messages,allowing the messages to be filed, listed, forwarded orreplied to.Generally a single user-interface program is used tosend and receive messages both locally and worldwide.Users do not need to have the same e-mail software

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program as the person they are corresponding with.The e-mail itself may consist of simply a message ormay carry with it attachments containing files createdin a variety of software applications, for example wordprocessed documents or spreadsheets.Electronic mail is a method for communicatingmessages electronically using computer networks.The ability to send email depends on having anInternet Service Provider and a modem, or being linkedinto a larger university, government or companynetwork.Being linked into a larger network requires a user tohave a network card in the computer and access tonetwork cabling. There are various networkingstandards.One of the most common is ‘ethernet’.Ethernet: A local area network (LAN) protocol thatsupports data transfer. Open networks allow users tosend e-mail internally, to colleagues in the sameorganisation, and externally via the Internet. Someorganisations have private networks that allow staff tosend e-mail all over the world, but not outside theorganisation.Network administrators or Internet Service Providerswill give users an email address.This is usually in the format xxx@yyy.zzz. The first partof the address before the @ sign is the individual user’sname or identifier. The second part of the address issplit into at least two parts (sometimes more), eachpart divided by a full stop or period.This part of the address indicates which company oruniversity the user works for, or which ISP they areusing, or even which country they are based in.

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For example a user on America-Online would have theaddress: auser@aol.com. A user in the BritishUniversity College London may have the email address:zzz999@ucl.ac.uk. In this address, the user has beengiven the code ‘zzz999’ by the university. The rest ofthe address shows that ‘ucl’ is University CollegeLondon, that it is an academic institution (‘ac’) and thatit is based in the UK (‘uk’). There are a number ofdifferent types of email addresses, including .com, .org,.co.uk and so on.The following figure is an example of an e-mailmessage received using Microsoft Outlook Expresselectronic mail software that includes attachments.

SOME ADDITIONAL INFORMATIONComputer keyboard shortcut keysQuick links

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Shortcut keys ABCsBasic PC shortcut keysF1 - F12 function keysTop 10 keyboard shortcutsLinux and Unix shortcut keysApple shortcut keysMicrosoft Windows shortcutsMicrosoft Excel shortcut keysMicrosoft Word shortcut keysInternet Explorer shortcut keysMicrosoft FrontPage shortcut keysMicrosoft Outlook shortcut keysMozilla FirefoxKeyboard termsHow do I create a Windows shortcut key?Shortcut keys ABCsShortcut keys help provide an easier and usuallyquicker method of navigating and using computersoftware programs. Shortcut keys are commonlyaccessed by using the Alt (on IBM compatiblecomputers), command key (on Apple computers), Ctrl,or Shift in conjunction with a single letter. The de factostandard for listing a shortcut is listing the modifierkey, a plus symbol, and the single character. In otherwords, "ALT+S" is telling you to press the Alt key andwhile continuing to hold the Alt key, press the S key toperform the shortcut.In addition to the shortcuts listed on this page, userscan find the shortcut keys to their most popularprogram by looking for underlined letters in theirmenus. For example, in the picture to the right you'llcannotice that the "F" in File has been underlined.This means you can press the Alt key and F to accessthe File menu. Note: Some programs require the userpress and hold ALT to see the underlined characters.

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Finally, as can also be seen some of the commonfeatures such as Open (Ctrl+O) and Save (Ctrl+S)have shortcut keys assigned to them.As you begin to memorize shortcut keys, you'll noticethat many applications share the same shortcut keys.We have the most commonly shared shortcut keys inthe below basic PC shortcut keys section.Tip: Users outside the United States or users using aforeign copy of a Microsoft Windows or Microsoftapplication may not be able to get all the belowshortcut keys to perform the function listed below.Basic PC shortcut keysThe below basic shortcut keys are a listing of shortcutkeys that will work with almost all IBM compatiblecomputers and software programs. It is highlyrecommended that all users keep a good reference ofthe belowshortcut keys or try to memorize the below keys. Doingso will dramatically increase your productivity.Shortcut Keys DescriptionAlt + F File menu options in current program.Alt + E Edit options in current programF1 Universal Help in almost every Windows program.Ctrl + A Select all text.Ctrl + F Open find window for current document orwindow.Ctrl + X Cut selected item.Shift + Del Cut selected item.Ctrl + C Copy selected item.Ctrl + Ins Copy selected itemCtrl + V PasteShift + Ins PasteCtrl + P Print the current page or document.Home Goes to beginning of current line.Ctrl + Home Goes to beginning of document.

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End Goes to end of current line.Ctrl + End Goes to end of document.Shift + Home Highlights from current position tobeginning of line.Shift + End Highlights from current position to end ofline.Ctrl + Left arrow Moves one word to the left at a time.Ctrl + Right arrow Moves one word to the right at atime.

Microsoft Word shortcut keysBelow is a listing of all the major shortcut keys in MicrosoftWord. See the computer shortcut page if you arelooking for other shortcut keys used in other programs.Shortcut DescriptionCtrl + 0 Adds or removes 6pts of spacing before a paragraph.Ctrl + A Select all contents of the page.Ctrl + B Bold highlighted selection.Ctrl + C Copy selected text.Ctrl + D Open the font preferences window.Ctrl + E Aligns the line or selected text to the center of thescreen.Ctrl + F Open find box.Ctrl + I Italic highlighted selection.Ctrl + J Aligns the selected text or line to justify the screen.Ctrl + K Insert link.Ctrl + L Aligns the line or selected text to the left of thescreen.Ctrl + M Indent the paragraph.Ctrl + P Open the print window.

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Ctrl + R Aligns the line or selected text to the right of thescreen.Ctrl + T Create a hanging indent.Ctrl + U Underline highlighted selection.Ctrl + V Paste.Ctrl + X Cut selected text.Ctrl + Y Redo the last action performed.Ctrl + Z Undo last action.Ctrl + Shift + L Quickly create a bullet point.Ctrl + Shift + F Change the font.Ctrl + Shift + > Increase selected font +1pts up to 12pt andthen increases font +2pts.Ctrl + ] Increase selected font +1pts.Ctrl + Shift + < Decrease selected font -1pts if 12pt or lower,if above 12 decreases font by+2pt.Ctrl + [ Decrease selected font -1pts.Ctrl + / + c Insert a cent sign (¢).Ctrl + ' + <char> Insert a character with an accent (grave)mark, where <char> is thecharacter you want. For example, if you wanted an accented èyou woulduse Ctrl + ' + e as your shortcut key. To reverse the accentmark use theopposite accent mark, often on the tilde key.Ctrl + Shift + * View or hide non printing characters.Ctrl + <left arrow> Moves one word to the left.Ctrl + <right arrow> Moves one word to the right.Ctrl + <up arrow> Moves to the beginning of the line orparagraph.Ctrl + <down arrow> Moves to the end of the paragraph.Ctrl + Del Deletes word to right of cursor.Ctrl + Backspace Deletes word to left of cursor.

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Ctrl + End Moves the cursor to the end of the document.Ctrl + Home Moves the cursor to the beginning of thedocument.Ctrl + Spacebar Reset highlighted text to the default font.Ctrl + 1 Single-space lines.Ctrl + 2 Double-space lines.Ctrl + 5 1.5-line spacing.Ctrl + Alt + 1 Changes text to heading 1.Ctrl + Alt + 2 Changes text to heading 2.Ctrl + Alt + 3 Changes text to heading 3.Alt + Ctrl + F2 Open new document.Ctrl + F1 Open the Task Pane.Ctrl + F2 Display the print preview.Ctrl + Shift + > Increases the highlighted text size by one.Ctrl + Shift + < Decreases the highlighted text size by one.Ctrl + Shift + F6 Opens to another open Microsoft Worddocument.Ctrl + Shift + F12 Prints the document.F1 Open Help.F4 Repeat the last action performed (Word 2000+)F5 Open the find, replace, and go to window in MicrosoftWord.F7 Spellcheck and grammar check selected text or document.F12 Save as.Shift + F3 Change the text in Microsoft Word from uppercaseto lowercase or acapital letter at the beginning of every word.Shift + F7 Runs a Thesaurus check on the word highlighted.Shift + F12 Save.Shift + Enter Create a soft break instead of a new paragraph.Shift + Insert Paste.Shift + Alt + D Insert the current date.Shift + Alt + T Insert the current time.

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In addition to the above shortcut keys users can also use theirmouse as a method of quickly do somethingcommonly performed. Below some are examples of mouseshortcuts.Mouseshortcuts DescriptionClick, hold,and dragSelects text from where you click and hold to the point youdrag and let go.Double-click If double-click a word, selects the completeword.Double-click Double-clicking on the left, center, or right of ablank line will make the alignment of thetext left, center, or right aligned.Double-click Double-clicking anywhere after text on a linewill set a tab stop.Triple-click Selects the line or paragraph of the text the mousetriple-clicked.Ctrl + Mouse Wheel Zooms in and out of document.

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