1. Computer Fundamentals & Hardware

1.1 Basic Block Diagram of a Computer

• Input Unit: Keyboard, Mouse, Scanner, Microphone, Webcam
• Processing Unit: CPU (Central Processing Unit)
• Output Unit: Monitor, Printer, Speaker, Projector
• Storage Unit: Primary (RAM, ROM) & Secondary (HDD, SSD, Pen Drive)

1.2 CPU Architecture

• ALU (Arithmetic Logic Unit): Performs arithmetic (+, -, ×, ÷) and logical (AND, OR, NOT) operations.
• CU (Control Unit): Directs data flow and instruction execution; does not perform calculations.
• Registers: Small, fast memory locations inside CPU (e.g., PC, ACC, MAR, MDR).

1.3 Memory Types

TypeVolatile?UseRAM (Random Access Memory)YesRunning programs, current dataROM (Read Only Memory)NoBoot firmware (BIOS/UEFI)Cache MemoryYesHigh-speed buffer between CPU and RAMRegisterYesImmediate data for CPU

1.4 Secondary Storage Devices

• HDD (Hard Disk Drive) – magnetic, high capacity, slower
• SSD (Solid State Drive) – flash memory, faster, no moving parts
• Optical Discs (CD/DVD/Blu-ray)
• Flash Drives / Memory Cards

1.5 Input/Output Devices – Key Points for Exam

• Printer types: Laser (toner), Inkjet (liquid ink), Dot Matrix (impact)
• Monitor types: LCD, LED, OLED – resolution, refresh rate
• Touchscreen technologies: Resistive (pressure), Capacitive (finger)

1.6 Data Storage Units (Important for Numerical Questions)

text

1 Bit = 0 or 1
1 Nibble = 4 bits
1 Byte = 8 bits
1 KB = 1024 Bytes = 2^10 Bytes
1 MB = 1024 KB = 2^20 Bytes
1 GB = 1024 MB = 2^30 Bytes
1 TB = 1024 GB = 2^40 Bytes
1 PB = 1024 TB = 2^50 Bytes

Exam tip: Know 2^10 = 1024. 1 GB = 2^30 B, 1 TB = 2^40 B, so 1024 TB = 2^50 B.

2. Operating Systems & System Software

2.1 Functions of an OS

• Process management, Memory management, File management, Device management, Security, User interface

2.2 Types of OS

• Batch, Time-sharing, Real-time, Distributed, Network OS, Mobile OS (Android, iOS)

2.3 Popular OS for Exams

• Windows (GUI, Control Panel, Registry)
• Linux (Open source, Kernel, Ubuntu, Fedora)
• macOS (Unix-based)

2.4 System Software vs Application Software

System SoftwareApplication SoftwareOS, Compiler, Assembler, DriverMS Word, Excel, Browser, GamesRuns in backgroundUser-interactive

2.5 Utility Software

• Antivirus, Disk Cleanup, Disk Defragmenter, Backup software, File compression (WinRAR, 7-Zip)

2.6 Control Panel Settings (Windows)

• Device Manager – hardware drivers
• Network and Sharing Center – IP, Wi-Fi
• User Accounts – password, family safety
• Programs and Features – uninstall
• System – RAM, processor, Windows version

3. Office Automation Tools (MS Office)

3.1 MS Word – Key Features & Shortcuts

• File Tab: New, Open, Save, Save As, Print, Share
• Home Tab: Clipboard, Font, Paragraph, Styles, Editing
• Insert Tab: Table, Picture, Shapes, Header/Footer, Page Number, Equation
• Page Layout: Margins, Orientation (Portrait/Landscape), Columns, Watermark
• Review Tab: Spell Check (F7), Thesaurus, Track Changes, Comments
• Shortcuts (highly asked):
• Ctrl + S – Save
• Ctrl + P – Print
• Ctrl + B – Bold
• Ctrl + I – Italic
• Ctrl + U – Underline
• Ctrl + C / X / V – Copy / Cut / Paste
• Ctrl + Z / Y – Undo / Redo
• Ctrl + A – Select all
• Ctrl + F – Find
• Ctrl + H – Replace
• F7 – Spell Check
• Ctrl + K – Insert hyperlink

3.2 MS Excel – Functions & Cell Referencing

• Basic Functions:
• SUM(range) – total
• AVERAGE(range) – mean
• COUNT(range) – number of numeric cells
• COUNTA(range) – non-empty cells
• MAX(range), MIN(range)
• IF(logical_test, value_if_true, value_if_false)
• VLOOKUP(lookup_value, table_array, col_index, [range_lookup])
• CONCATENATE() or & – join text
• Cell Referencing (critical for exam):
• Relative (A1) – changes when copied
• Absolute ($A$1) – does not change
• Mixed ($A1 or A$1) – one part fixed
• Charts:
• Column, Bar, Line, Pie, Area, Scatter
• Chart elements: Title, Legend, Axis, Data labels
• Shortcuts:
• Ctrl + ; – current date
• Ctrl + Shift + ; – current time
• Alt + = – AutoSum

3.3 MS PowerPoint – Slide Views & Animations

• Views: Normal, Outline, Slide Sorter, Notes Page, Reading View, Slide Show (F5)
• Transitions: Effects when moving from one slide to the next
• Animations: Effects on individual objects (Entrance, Emphasis, Exit, Motion Paths)
• Animation Pane: Order and timing control
• Master Slide: Change font/logo for all slides at once
• Shortcuts:
• F5 – start slide show from beginning
• Shift + F5 – from current slide
• Ctrl + M – new slide

4. Networking & Internet

4.1 IP Address & MAC Address

• IP Address: Logical address (IPv4: 32-bit, e.g., 192.168.1.1; IPv6: 128-bit)
• MAC Address: Physical address (48-bit, e.g., 00:1A:2B:3C:4D:5E) – burned into NIC

4.2 Network Scales

TypeRangeExamplePAN (Personal Area Network)Few metersBluetooth, USBLAN (Local Area Network)Building/CampusOffice, School labMAN (Metropolitan Area Network)CityCable TV networkWAN (Wide Area Network)Country/WorldInternet

4.3 Internet Protocols (Important)

ProtocolFull FormPortUseHTTPHyperText Transfer Protocol80Web pagesHTTPSHTTP Secure443Secure webFTPFile Transfer Protocol21File upload/downloadSMTPSimple Mail Transfer Protocol25Sending emailPOP3Post Office Protocol v3110Receiving emailIMAPInternet Message Access Protocol143Email syncDNSDomain Name System53Converts domain → IPDHCPDynamic Host Configuration Protocol67/68Auto IP assignment

4.4 Wi-Fi / 5G Technologies

• Wi-Fi Standards: 802.11a/b/g/n/ac/ax (Wi-Fi 6)
• Bands: 2.4 GHz (range) & 5 GHz (speed)
• 5G: 5th generation mobile network – low latency, high speed, massive IoT

4.5 Email Mechanics

• Email header: From, To, Date, Subject, Return-Path
• CC (Carbon Copy) – visible to all
• BCC (Blind Carbon Copy) – recipients hidden from each other
• Attachment – file sent with email (size limits)
• Spam – unsolicited bulk email
• Phishing email – fake email to steal credentials

5. Cybersecurity

5.1 Threats & Attacks

ThreatDescriptionMalwareMalicious software (virus, worm, trojan, ransomware)VirusAttaches to clean files; requires user actionWormSelf-replicates without user actionTrojanDisguised as legitimate softwareRansomwareEncrypts data; demands paymentPhishingFake emails/websites to steal infoSocial EngineeringManipulating people to give secretsDoS/DDoSOverwhelming a server with traffic

5.2 Defense Tools

• Firewall: Filters network traffic (hardware or software)
• Antivirus/Antimalware: Scans and removes malicious code
• Multi-Factor Authentication (MFA): Two or more verification methods (password + OTP + biometric)
• Encryption: Converts plaintext to ciphertext (AES, RSA)
• VPN (Virtual Private Network): Encrypts all internet traffic

5.3 Security Best Practices

• Strong, unique passwords
• Regular software updates
• Backup data
• Avoid unknown links/attachments
• Use HTTPS

6. Emerging Technologies (AI, Cloud, VR)

6.1 Artificial Intelligence (AI)

• Machine Learning (ML): Systems learn from data without explicit programming.
• Supervised, Unsupervised, Reinforcement learning
• Natural Language Processing (NLP): Enables computers to understand human language (e.g., ChatGPT, Google Translate)
• Generative AI: Creates new content (text, images, music)
• ChatGPT – text generation
• DALL-E – image generation from text
• Midjourney, Stable Diffusion

6.2 Cloud Computing

• Service Models:
• IaaS (Infrastructure as a Service) – virtual machines, storage (AWS EC2)
• PaaS (Platform as a Service) – deploy apps without managing OS (Google App Engine)
• SaaS (Software as a Service) – software over internet (Google Drive, Office 365)
• Deployment:
• Public, Private, Hybrid, Community cloud
• Advantages: Scalability, pay-as-you-go, accessibility

6.3 Blockchain

• Decentralized, distributed ledger
• Each block contains transactions + cryptographic hash
• Used in: Cryptocurrency (Bitcoin), Smart contracts, Supply chain

6.4 Virtual Reality (VR) & Augmented Reality (AR)

• VR: Fully immersive digital environment (headset)
• AR: Overlays digital content on real world (Pokémon GO, Snapchat filters)
• MR (Mixed Reality): Merges real and virtual worlds

7. ICT in Nepal (History & Policies)

7.1 Historical Development

• 1970s: First computers introduced in Nepal (IBM 1401 at HMG)
• 1980s: Computer education started in TU, Institute of Engineering
• 1990s: Internet access begins (Mercantile Communications, 1995)
• 2000s: Growth of ISPs, cyber laws, e-governance

7.2 Major ISPs in Nepal

• WorldLink
• Subisu (now part of CG Net)
• Classic Tech
• Vianet
• Nepal Telecom (ADSL, Fiber)
• CG Net (Fiber)

7.3 One Laptop Per Child (OLPC) Program

• Launched in Nepal in 2008 (pilot in remote schools)
• Aim: Provide low-cost XO laptops to primary students in developing countries
• Impact: Mixed – infrastructure challenges, but increased digital awareness

7.4 National AI Policy (Nepal)

• Status: Draft prepared (2020 onward); not yet fully implemented
• Objectives:
• Promote AI research and development
• Use AI in agriculture, health, education, tourism
• Build AI workforce
• Ethical guidelines for AI
• Related: Digital Nepal Framework (2019) – 80 initiatives across 8 sectors

7.5 Other ICT Policies

• IT Policy 2072 (2015) – focus on software industry, IT parks
• Cyber Law of Nepal – Electronic Transaction Act (ETA) 2063 (2008)
• National Broadband Policy – expand internet access to rural areas