This document provides an introduction to computer systems by discussing the four phases of the information processing cycle, the four categories of computer hardware, units of measure for computer memory and storage, common input and output devices, and the two main categories of computer software. It also defines key concepts like data, information, programs, and the roles of users with personal computers.

1. CSE 1101- Introduction to Computer
Looking Inside into Computer System

2. Objectives
A complete computer system
Four phases of the information processing cycle
Four categories of computer hardware
Units of measure for computer memory and storage
Common input and output devices
Storage devices
Two main categories of computer software
Difference between data, information and program
Role of user with PC

3. A complete computer system
1. Hardware
It refers to the physical and visible components.
2. Software
It is used to control a computer.
3. Data
Any set of characters that is gathered and translated for
some purpose, usually analysis.
4. Users
Differences between Hardware and Software?

4. Von Neumann Architecture
Program instructions
and data share the same
memory and pathways.
An instruction fetch and
a data operation cannot
occur at the same time

5. Harvard Architecture
It contains separate
storage and separate
buses (signal path) for
instruction and data.
CPU can access
instructions and
read/write data at the
same time.
Von Neumann Vs. Harvard Architecture

6. Four phases of the information
processing cycle
1. Input
Computer receives data from input source by user or a program
2. Processing
After receiving data, here the computer performs actions on the data
like mathematical operations or logical comparisons etc. as per being
instructed by user or a program.
3. Output
After processing the data computer has generated information that now
can be sent to output.
4. Storage
After processing the data, computer can also store the data into an
storage device for future use.

7. Four categories of computer
hardware
1. Input Devices:
For raw data input.
2. Processing Devices:
To process raw data to generate useful information.
3. Output Devices:
To disseminate data and information.
4. Memory/Storage Devices:
Like memory devices but they are different as storage devices
can keep data when the computer is turned off, can be used to store data
both by a program and an user.

8. Units of measure for computer
memory and storage
Unit Abbreviation
Actual Value
(bytes)
Kilobyte KB 1,024
Megabyte MB 1,048,576
Gigabyte GB 1,073,741,824
Terabyte TB 1,099,511,627,776

9. Common input and output devices
Input devices
◦ Keyboard, Mouse, microphone
◦ Trackball, touchpad, joystick
◦ Scanner, digital camera
Output devices
◦ Monitor, printer
◦ Speaker
Both input and output devices
◦ Communication devices e.g. modem

10. Communication Devices
Networking is the process of connecting one computer to
another.
Modem: A modem converts digital (computer readable) data
to analog signals (e.g., telephone, television) and analog to
digital.
Network interface cards (NICs): Digital-to-digital hardware
components that allow communication and can uniquely
identify the computing device on the network.

11. Primary Memory
RAM (Random Access Memory)
◦ It is the fastest type of memory.
◦ It is a temporal storage memory. RAM is volatile that only
retains all the data as long as the computer powered.
◦ RAM stores the currently processed data from the CPU and
sends them to the graphics unit.
ROM (Read Only Memory)
◦ “Non-Volatile Memory” that retains data without the flow of
electricity.
◦ ROM comes with pre-written by the computer manufacturer to
hold the instructions for booting-up the computer.

12. Storage Device
Magnetic storage
• Magnetic disks (Device: removable disk drive)
o E.g. Floppy disks
• Hard disk (device: non removable Hard drive)
Optical storage
• Compact Disk (CD)(device: CD-ROM, CD-RW)
• Digital Video Disk (DVD) (device: DVD players)

13. Computer Software
Software is a collection of instructions, data, or computer
programs used to run computers and carry out particular
activities.
System Software:
◦ Between the user and the hardware, it serves as a middle layer or
mediator. It runs in the background of a device.
Application Software:
◦ It aids users in completing tasks including research, note-taking,
alarm setting, graphic design, and account log maintenance.

14. Two main categories of computer
software
1. System software 2. Application software
i. Operating system
ii. Network operating
system
iii. Utility
i. Word processing
ii. Spreadsheet
iii. Database
iv. Presentation
v. Graphics
vi. Multimedia
vii. Entertainment and
Education
viii.Web design
ix. Games

15. Why Software is Important?
Maximizes the Full Potential of Hardware
◦ The most cutting-edge hardware in computing means nothing if
there is no software to run on it.
Provides an Intuitive Interface to Work With
◦ The way we interact with our gadgets is predetermined by the
software running on them, so it's clear how crucial it is.
Promotes Innovation and Collaboration
◦ People can now transfer critical information and instructions
regardless of distance.
Boosts Efficiency and Productivity

16. Difference between data,
information and program
Data Information Program
Piece of information
without context
Data placed in
context
Set of instructions
that tells the
computer how to
perform tasks

17. Role of user with a PC
Setting up the system
Installing Software
Running Program
Managing Files
File hierarchy
File manager

18. Thank You!!!