This document discusses the basic components and functions of a computer system. It describes a computer as a device that responds to specific instructions to perform well-defined tasks like adding numbers. The three main units are the CPU, input devices, and output devices. The CPU contains the control unit, ALU, and memory to process data. Input devices like keyboards and mice feed data into the computer. Output devices such as monitors, printers, and speakers send processed information from the CPU out of the computer.

4. INTRODUCTION

5. Its principal characteristics are:
 RESPONDS TO SPECIFIC SET OF INSTRUCTIONS IN
A WELL DEFINED MANNER.
 E.G. INSTRUCTION TO ADD 2 NUMBERS.
 PRE RECORDED LIST OF INSTRUCTION I.E A
PROGRAM.(SOFTWARE LIKE MS WORD)

6. THREE UNITS
 CPU
 INPUT DEVICES
 OUTPUT DEVICES

7. CPU

8. DATA PROCESSING
 DATA PROCESSING, MANIPULATION OF DATA BY
A COMPUTER. IT INCLUDES THE CONVERSION
OF RAW DATA TO MACHINE-READABLE FORM,
FLOW OF DATA THROUGH THE CPU AND
MEMORY TO OUTPUT DEVICES, AND
FORMATTING OR TRANSFORMATION OF
OUTPUT. ANY USE OF COMPUTERS TO PERFORM
DEFINED OPERATIONS ON DATA CAN BE
INCLUDED UNDER DATA PROCESSING.

9. The Control unit

11. ALU
 Its used to perform arithmetic and logic operations.
 IT CONTROLS the speed of calculations.

12. Internal Memory
 It’s a primary storage or main memory

13. Registers And Addresses

14. Registers
 Computers also have several additional storage
locations called registers.
 Registers are special areas that hold data and
instructions temporarily during processing.
 They are parts of control unit and ALU.

15. Addresses
To locate the data or instructions in
the main memory, the computer
stores them in location known as
addresses.

16. ARE THOSE WHICH FEEDS DATA INTO
COMPUTER AND SENDS INFORMATION TO
CPU TO PERFORM SPECIFIC OPERATIONS.
MOST COMMON ONE IS KEYBOARD AND
MOUSE.

17. TYPES OF INPUT DEVICES
 THE KEYBOARD
 MOUSE
 TRACKBALL
 JOYSTICKS
 DIGITIZING TABLET
 SCANNERS
 DIGITAL CAMERA

18.  MICR-MAGNETIC INK
CHARACTER RECOG
 OCR-OPTICAL
CHRACTER
RECOGNITION
 OMR-OPTICAL MARK
RECOGNITION

19.  BAR CODE READER
 SPEECH INPUT
DEVICES.
 TOUCH SCREEN
 TOUCH PAD
 LIGHT PEN

20. ANY DEVICES THAT OUTPUTS
INFORMATION FROM COMPUTER IS
CALLED AN OUT PUT DEVICES.

21. TYPES OF OUT PUT DEVICES ARE:
 MONITOR
 PRINTER
 PLOTTER
 SOUND CARDS AND SPEAKERS.