ICT Lecture Review

1. BY: Sadaf Mehmood
Associate Lecturer
Uog Sialkot

2. “A computer is an electronic machine that has the capability to
perform certain types of processing/computation on the supplied data.
It can also store the data as well as generated results.”
• Device that execute all the sequence of instructions
Information processing cycle:
Storage
Processing/
Computation
Data & Instructions Information/Results

3.  The data(raw fact & figure) consists of numbers, text, sound, images,
animations, and video.
 Instruction: direction or order about how something should be done.
 The process converts numbers, text, sound, images, animations, and
video (data) into usable data, which is called information.
 The information consists of numbers, text, sound, images, animations,
and video that has been converted by the process.
 The data is inserted using an input device.
 The central processing unit (CPU) converts data to information.
 The information is put on an output device.

4. Computer
Hardware Software
Application
Software
System
Software
CPU Memory I/O Etc.

5.  Computer Hardware
 Electric, electronic, and mechanical devices
 Computer Software
 Programs and data in electronic form on a storage medium
 Program- Sequence of Instructions

7.  Input devices
 Processor & Memory
 Storage devices
 Output devices

8.  Mouse
 Keyboard
 Joystick
 Camera
 Microphone

9.  Peripheral Devices:
 That is connected outside/separatly the computers.
 Printer - laser, inkjet
 Speakers
 Keyboard
 Mouse
 Monitor - CRT, LCD, projector

10.  Pentium
 8086
 Celeron
 SPARC
 Alpha
What are Control Unit and ALU?
The arithmetic/logic unit (ALU) contains the electronic circuitry that
executes all arithmetic and logical operations.
The control unit (CU) of the CPU contains circuitry that uses
electrical signals to direct the entire computer system to carry out,
or execute, stored program instructions.

11.  What is storage?
 Holds data, instructions, and information
for future use
 Secondary memory: where programs and data are kept
on a long term bases
 Hard disk
 Floppy
 CD
 DVD
 Primary memory: where programs and data are kept
temporarily while a computer is running and that is
directly access by the CPU
 Cache
 System ROM
 Processor/RAM

12. Memory:
Consists of electronic components that store
instructions waiting to be executed and data needed by
those instructions.
 RAM (random access memory)
 Located on mother board
 Volatile memory(all information is lost when the computer is turned off)
 Cache
 Store program and instruction that are repeatedly by the CPU can be accessed quickly as
compared to main memory/primary memory
Virtual Memory?
memory management capability of OS compensate of
physical memory shortages by temporarily transferring data
from RAM to disk storage.

13.  Bit - a binary digit e.g. 1 or 0
 Byte - a binary word consisting of 8 bits
 Kilo Byte - 1024 bytes
 Mega Byte - 1024 KB
 Giga Byte - 1024 MB
 Tera Byte - 1024 GB

15. Keyboard Mouse
PrinterRAM/ROM
HD
Mem
Bus
System Bus
Monitor
CD
Processor
Floating Point
Unit
Integer
Unit
Cache
Control
Unit
BUS (two type Data & Instruction buses)

16.  System Software:
 Controls the computer
 Performs the basic operating tasks
 E.g Operating System(Windows, Linux, Ubunto)
 Application Software:
 Help user to accomplish a specific task
 MS word, MS Excel, Calculator, Games, Google

17. Application Software
System Software
Hardware
Few Basics: Figure

18. Operating systems
 Works as coordinator between hardware and user
software Example: Opening a word document,
screen display, print, and save.
 Allocates system resources (CPU, peripherals)
Examples: use of key board, mouse, playing music,
displaying on monitor
Few Basics: System Software

19. Utility Software
 Is a system software designed to help to
analyze configure optimize or maintained a
computer.
 Example: Anti viruses, backup, disk repair,
disk cleaner, file manager
Few Basics: System Software

20. Device Drivers
 The system software that helps computer control a
peripheral device. Usually supplied by the vendor
of the computer device
 Example: DD for mouse, DD for Laser printer
Few Basics: System Software