Bsc.CSIT Entrance Notes

Bsc-csitGeneral ItUpdated: 5/7/2026
BSc CSIT ENTRANCE GENERAL IT NOTES
The IT section measures your understanding of basic computer and digital concepts crucial for CSIT study.
1. INTRODUCTION TO COMPUTER
Definition
A computer is an electronic device that accepts data, processes it, stores it, and produces meaningful information.
Characteristics of Computer
  • Speed
  • Accuracy
  • Automation
  • Storage
  • Reliability
  • Versatility
Basic Components of Computer
Input Unit
Used to enter data into computer.
Examples:
  • Keyboard
  • Mouse
  • Scanner
Processing Unit
Processes data and instructions.
$$ CPU = \text{Central Processing Unit} $$
Output Unit
Displays processed information.
Examples:
  • Monitor
  • Printer
  • Speaker
Storage Unit
Stores data and programs.
Examples:
  • Hard Disk
  • SSD
  • Pen Drive
2. SOFTWARE
Definition
Software is a collection of programs and instructions.
Types of Software
System Software
Controls hardware and system operations.
Examples:
  • Operating System
  • Device Drivers
Application Software
Used to perform specific tasks.
Examples:
  • MS Word
  • Photoshop
  • Browser
Operating System
Acts as an interface between user and hardware.
Examples:
  • Windows
  • Linux
  • macOS
3. PROGRAMMING CONCEPTS
Program
A set of instructions written to solve problems.
Programming Language
A language used to write computer programs.
Types of Programming Languages
Type
Example
Low Level Language
Assembly
High Level Language
C, Java, Python
Algorithm
Step-by-step procedure to solve a problem.
Flowchart
Graphical representation of algorithm.
Compiler
Converts high-level language into machine language.
Interpreter
Executes program line by line.
4. COMPUTER FUNDAMENTALS
Data
Raw facts and figures.
Information
Processed and meaningful data.
Memory Units
Unit
Value
1 Byte
8 bits
1 KB
1024 Bytes
1 MB
1024 KB
1 GB
1024 MB
Types of Memory
Primary Memory
  • RAM
  • ROM
Secondary Memory
  • HDD
  • SSD
  • CD/DVD
RAM
Temporary memory.
$$ RAM = \text{Random Access Memory} $$
ROM
Permanent memory.
$$ ROM = \text{Read Only Memory} $$
5. MULTIMEDIA
Definition
Combination of text, audio, video, graphics, and animation.
Components of Multimedia
  • Text
  • Image
  • Audio
  • Video
  • Animation
Applications of Multimedia
  • Education
  • Entertainment
  • Advertising
  • Communication
6. INTERNET
Definition
A worldwide network connecting millions of computers.
Uses of Internet
  • Communication
  • Research
  • Online Learning
  • E-Commerce
  • Social Networking
Internet Services
  • Email
  • WWW
  • File Transfer
  • Video Conferencing
7. WORLD WIDE WEB (WWW)
Definition
A collection of interconnected web pages.
Web Browser
Software used to access websites.
Examples:
  • Chrome
  • Firefox
  • Edge
Website
A collection of related web pages.
URL
$$ URL = \text{Uniform Resource Locator} $$
Used to identify web addresses.
8. EMAIL
Definition
Electronic mail used for digital communication.
Components of Email
  • To
  • CC
  • BCC
  • Subject
  • Attachment
Advantages of Email
  • Fast communication
  • File sharing
  • Low cost
9. SOCIAL MEDIA
Definition
Digital platforms used for communication and content sharing.
Examples
  • Facebook
  • Instagram
  • YouTube
  • X (Twitter)
  • LinkedIn
Advantages
  • Communication
  • Marketing
  • Education
Disadvantages
  • Privacy issues
  • Addiction
  • Fake news
10. E-GOVERNANCE
Definition
Use of information technology in government services.
Objectives
  • Transparency
  • Efficiency
  • Fast service delivery
Examples
  • Online tax payment
  • Digital citizenship services
  • Online license system
11. DIGITAL FINANCE TOOLS
Definition
Digital systems used for financial transactions.
Examples
  • Mobile Banking
  • eSewa
  • Khalti
  • ConnectIPS
  • Internet Banking
Advantages
  • Fast transactions
  • Easy payment
  • Reduced cash handling
Security Measures
  • Strong password
  • OTP verification
  • Two-factor authentication
12. CYBERSECURITY
Definition
Protection of computer systems and data from attacks.
Common Cyber Threats
Threat
Description
Virus
Malicious software
Malware
Harmful programs
Phishing
Fake message scam
Hacking
Unauthorized access
Antivirus
Software used to protect computer systems.
Cyber Safety Rules
  • Use strong passwords
  • Avoid suspicious links
  • Update software regularly
  • Do not share OTP/password
13. NUMBER SYSTEM
Decimal Number System
Base:
$$ 10 $$
Digits:
$$ 0-9 $$
Binary Number System
Base:
$$ 2 $$
Digits:
$$ 0,1 $$
Octal Number System
Base:
$$ 8 $$
Digits:
$$ 0-7 $$
Hexadecimal Number System
Base:
$$ 16 $$
Digits:
$$ 0-9,A-F $$
Binary to Decimal Conversion
Example:
$$ (1011)_2 $$
$$ =1\times2^3+0\times2^2+1\times2^1+1\times2^0 $$
$$ =11_{10} $$
14. BOOLEAN LOGIC
Definition
Boolean logic deals with true and false values.
Boolean Values
$$ 1 = \text{True} $$
$$ 0 = \text{False} $$
Basic Logic Gates
Gate
Symbol
AND
$\cdot$
OR
$+$
NOT
$\overline{A}$
AND Gate
$$ Y=A\cdot B $$
Truth Table:
A
B
Y
0
0
0
0
1
0
1
0
0
1
1
1
OR Gate
$$ Y=A+B $$
NOT Gate
$$ Y=\overline A $$
IMPORTANT COMPUTER TERMS SUMMARY
CPU
$$ CPU = \text{Central Processing Unit} $$
URL
$$ URL = \text{Uniform Resource Locator} $$
RAM
$$ RAM = \text{Random Access Memory} $$
ROM
$$ ROM = \text{Read Only Memory} $$
Binary Number System
$$ Base = 2 $$
Boolean Values
$$ 1=True $$
$$ 0=False $$