Slide 1Vision Today
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Evolution of Computers
To learn about the architecture of computers
Discuss the Disadvantages of the Computer
To become familiar with your computing environment
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Definition :
A computer is an electronic device, operating under the control of instructions (software) stored in its own memory unit, that can accept data (input) from the user, manipulate data (process), and display information (output) from the processing.
Generally, the term is used to describe a collection of devices that function together as a system.
Electronic information processing device. (includes storage & retrieval).
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Simply Defined as ,
Computer is an Electronic device used to store, retrieve and manipulate the data
Computer programs
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For giving Accurate Results
For doing variety of jobs at the same time
Performs computations and makes logical decisions
For producing Results in a printed form
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Why Is A Computer So Powerful?
The ability to perform the information processing cycle with amazing speed
Reliability (low failure rate)
Ability to communicate with other computers
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Charless Babbage is considered to be the FATHER Of Modern Digital Computer
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Printer (output)
Monitor (output)
Speaker (output)
Scanner (input)
Mouse (input)
Keyboard (input)
System unit
(processor, memory…)
Storage devices
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Accuracy
Dilligence
Versatility
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CONTROL UNIT
OUTPUT UNIT
Data Flow
---> Control Instructions
Input unit
- Mouse, keyboard,Scanner
Output unit
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Arithmetic and logic unit (ALU)
- Performs calculations
Secondary storage unit
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Computers can perform four general operations, which comprise the information processing cycle.
Input
Process
Output
Storage
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No thinking Power. That means not capable of taking independent decisions
Regular Maintenance is required
Disadvantages of Computers
- Discuss about Hardware & Software
Discuss about the following
- CPU,Microprocessor
Hardware
Software
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The Keyboard
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The Mouse
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Output Devices
Output devices make the information resulting from the processing available for use. The two output devices more commonly used are the printer and the computer screen.
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CPU & Peripheral Devices (Brain, Capacity, speed, store)
Named on model : 80286, 80386, 80486, Pentium, Pentium II to PIV (HEX in future?)
Clock Speed: 30-400 MHZ/sec.
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Program : Is a set of instructions to computer. Ex: Game, Ms-Word, Ms-Excel,
Data : Information created by user Ex : letter typed. Program is like typewriter and Data is the Letter typed by it.
Both are stored separately on the hard disk
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Tailor made & customized to requirements
Examples
Hardware
Software
It is the physical unit of the computer
It is a collection of programs to bring the hardware system into operation
It is the heat of the computer
It is the brain of the computer
It has permanent structure and cannot be altered
It has no permanent structure. So, it can be altered and reused
It is normally affected by agents like dust, heat, humidity etc.,
It is normally affected by agents like virus
It works with binary code, the presence or absence of pulses as 1’s or 0’s
It is represented by the higher level languages such as C,C++,VB etc.,
It can be touched and felt
It cannot be touched and felt
Keyboard,Mouse,CD-ROM,CPU,Monitor are Some Examples
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Data and Information
Data is a collection of raw facts, figures and symbols, such as numbers, words, images, video and sound, given to the computer during the input phase.
Computers manipulate data to create information. Information is data that is organized, meaningful, and useful.
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computer
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How Does a Computer Know what to do?
It must be given a detailed list of instructions, called a compute program or software, that tells it exactly what to do.
Before processing a specific job, the computer program corresponding to that job must be stored in memory.
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performance
Writes to and reads from every memory location
available in RAM
Uses the input and output device drivers to check for and initialize all available I/O devices including keyboard, video, sound and disk drives
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Database - MS Access, SQL Server
Graphics - MS Paint,Photoshop,Flash
Entertainment - Games,Video, Music
Informational - Educational software
Usually temporary (easily lost)
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Auxiliary storage devices are used to store data when they are not being used in memory. The most common types of auxiliary storage used on personal computers are floppy disks, hard disks and CD-ROM drives
Secondary Memory
(like food in the refrigerator)
Usually long-term (safer)
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Holds Windows, software, and most data
Usually don’t see it because it’s inside computer
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Holds large amount of data
Same technology as a music disk.
Not available on library computers
Compact Disc Read Only Memory
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A compact disk (CD), also called an optical disc, is a flat round, portable storage medium that is usually 4.75 inch in diameter.
A CD-ROM (read only memory), is a compact disc that used the same laser technology as audio CDs for recording music. In addition it can contain other types of data such as text, graphics, and video.
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Most recent widely used storage system
Very portable, often worn like jewelry
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5 megabytes
20 gigabytes
1 terabyte ( TB )
2 petabytes
20 petabytes
200 petabytes