itgs – software basic

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ITGS – Software Basic

Food for Thought:• Recipe for food• Precise steps• How many steps

Processing with Programs 1

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ITGS – Software Basic

Food for Thought:• One step to explain many actions

Processing with Programs 2

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ITGS – Software Basic

Computers – smart or intelligent machinesbut they perform only basic arithmetic operations

Computers – fast, smart machines

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ITGS – Software Basic

Algorithm is set of step-by-step procedures for accomplishing a task.

Programmers turn algorithms into programs by adding details, testing procedures and debugging – correcting errors.

Algorithm

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ITGS – Software Basic

Every computer processes instructions in a native machine language.

Machine language uses numeric codes to represent the most basic operations-adding, comparing, moving numbers and repeating instructions.

The Language of Computers 1

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ITGS – Software Basic

Early programs were written in machine language.

Nowadays, programming languages are like human languages.

High-level languages: C++, Java, Visual Basic.Net

The Language of Computers 2

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ITGS – Software Basic

Computer understands only machine language. High-level languages are easy for use for human.

High-level languages must be translated to the zeros and ones of machine language.

A translator program 1

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ITGS – Software Basic

A translator program converts the English-like instructions to the zeros and ones of machine language.

Translation process must be finished before using program.

A translator program 2

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ITGS – Software Basic

A translator programs are divided:

- compiler – translates file (formed .exe executive file). Complete translation before the first run (execution).

- interpreter each time when its run translate instruction. (instruction by instruction)

A translator program 3

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InputProgram (Source file) Compiler

Output:Program (Exe file)

ITGS – Software BasicTranslation processes 4

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InputStatement (each) Interpreter

Output:Statement (each)

ITGS – Software BasicTranslation processes 5

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ITGS – Software Basic

Software package includes printed documentation• Tutorial manuals• Reference manuals (how to use software)• Help (printed, on CD, DVD, computer or online)

Documentation

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ITGS – Software Basic

New version6.06.17.0

Update:• New versions

Upgrading

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ITGS – Software Basic

No complete, universal software standards exist in computer world.

Problem: program written for one type of computer system may not work on another.Windows 9x

Compatibility 1

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ITGS – Software Basic

Software - Microsoft:• DOS• Windows

• Office (documents)

Compatibility 2

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ITGS – Software Basic

Most programs works amazingly well but not perfectly.

Disclaimers

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ITGS – Software Basic

Applications designed specifically for a particular business or industry are called vertical-market or custom applications. (restaurant-management software, medical-billing software, school evidence software)Cost far more then mass-market applications.

Vertical Market and Custom Software

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ITGS – Software Basic

System software:• Operating system (OS)• Utility programs• Links• Compilers

Operating system 1

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ITGS – Software Basic

Operating system (OS):• Part of system software• Work behind the scenes

Operating system 2

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ITGS – Software Basic

Operating system communicating with:• screens• printers• disk drives• other peripheral devices OS communicate with peripherals and with user

Operating system 3

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ITGS – Software Basic

Operating system - concurrent processing of jobs :Rapidly switching back and forth between jobs (waiting for input, or printer, …)Time sharing:

OS Concurrent Processing of Jobs

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ITGS – Software Basic

Operating system communicating with:• screens• printers• disk drives• other peripheral devices OS communicate with peripherals

OS Communicate

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ITGS – Software Basic

Several jobs concurrently: OS must keep track• Divide memory • Swap information between the computer’s memory and external storage devices (access time slower)

Memory Management

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ITGS – Software Basic

Several jobs concurrently: OS must keep track

Data Management

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ITGS – Software Basic

Utility programs serve as tools for doing system and repairs that aren’t automatically handled by the operating system. Copy files, repair damaged data files, translate files to different programs, compress files, …Operating systems invoke many utility programs

Programs and Data Drivers

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ITGS – Software Basic

PC operating systems, created for the Apple II, the original IMB PC and other machines, looked nothing like today’s Macintosh and Windows operating systems. It was OS a character-based interface.A command line systems.

Desktop Operating Systems 1

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ITGS – Software Basic

Graphic display; is not limited to displaying rows and columns of characters, it can individually control every dot on the screen.The MAC OS a graphical user interface-abbreviated GUI (gooey)

Desktop Operating Systems 2

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ITGS – Software Basic

The first to market, the Macintosh was eclipsed in the GUI operating system. At the beginning MS Windows was a program (shell) that put graphical face on MS DOS. With Windows 95 MS transforming Windows from an operating system shell into full operating system.

Desktop Operating Systems 3

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ITGS – Software Basic

Hierarchical menus in Windows Mac OS organization (frequently needed commands into compact).Pop-up menusContext-sensitive menus

Desktop Operating Systems 4

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ITGS – Software Basic

Unix operating system developed at Bell Labs over a decade before the first PCs, enables a timesharing computer to communicate with several other computers or terminals at one time.UNIX is command line, character-based operating system.

Multiple-User Operating systems: Unix and Linux

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ITGS – Software BasicUsing a Linux GUI

Goal: GNOME, a shell that puts a graphical desktop environment between you and the Linux command-line environment.Tools: Linux, GNOME, OpenOffice

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ITGS – Software BasicHardware and Software Platforms 1

Microsoft Windows XP (2001) • Home edition; home users• Windows XP Professional (business users)• Windows XP Tablet PC Edition (Tablet PC-style notebooks)• Windows XP Media Center Edition (multimedia-enabled PCs)

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ITGS – Software BasicHardware and Software Platforms 2

Microsoft Windows XP is enhanced version of Windows 2000 Professional. Both Windows XP and Windows 2000 are technically successors to Windows NT, not Windows 9x/DOS.

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ITGS – Software BasicHardware and Software Platforms 3

Microsoft Server 2003 server-based counterpart to Windows XP successor to the Windows 2000 Server product family, runs on all sizes of Web servers.

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ITGS – Software BasicHardware and Software Platforms 4

Microsoft Windows Millennium Edition. (Windows Me)/Windows9x. The end of the DOS–based Windows versions. (Windows 3.1x; Windows 95; Windows 98;

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ITGS – Software BasicHardware and Software Platforms 5

Microsoft Windows CE.NET is designed mostly for embedded connecter devices, and a special versions of the OS, handheld computers like the Pocket PC.

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ITGS – Software BasicHardware and Software Platforms 6

•Palm OS•Mac OS X(20)•Mac OS 9•Linux, Sun Solaris and other UNIX variants. Linux is free, but doesn’t offer applications programs as Windows does.

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ITGS – Software BasicHardware and Software Platforms 7

Operating systems need application software so they can do useful work. Application software needs to be built to any kind of platform. Platform is combination of hardware and operating system software.Cross-platform applications (MS Office, Photoshop, are available in similar versions for multiple platforms.

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ITGS – Software BasicHardware and Software Platforms 8

Three general platforms: • Windows• Mac OS (graphic design, publishing, music, video, multimedia)• UNIX/Linux (servers and high-end workstations)

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ITGS – Software BasicHardware and Software Platforms 9

Three OS: • Windows (Intel or compatible CPU)• Mac OS (Power PC processors)• UNIX/Linux (can run on many hardware platforms, including Intel and Power PC processors) but different versions of Linux aren’t necessarily compatible.

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ITGS – Software BasicHardware and Software Platforms 10

Emulation, blurs the line between platforms.

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ITGS – Software BasicHardware and Software Platforms 11

Network vs. desktopMore time on the Web

Microsoft’s .NET strategy is a response to the popularity of Java, a platform-neutral computer language developed. Program written in Java can run on different OS.

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ITGS – Software BasicPassword

Changing lettersName of hacker programs used for getting in programHow to keep security of password? (hardware, software)