IT & Communication TechnologyIT & Communication Technology

Core concepts of computer hardware, software, memory hierarchy, and numbering systems essential for objective exams.

• CPU Architecture: The Central Processing Unit consists of the Arithmetic Logic Unit (ALU), Control Unit (CU), and Registers. It executes instructions stored in the primary memory.
• Memory Hierarchy: Registers and Cache memory are the fastest and most expensive, followed by Primary Memory (RAM/ROM), and Secondary Memory (HDD/SSD) which is slowest and cheapest.
• Volatile vs Non-Volatile Memory: RAM (Random Access Memory) is volatile (loses data on power loss), whereas ROM (Read Only Memory) and Flash memory are non-volatile.
• Operating System (OS): An OS acts as an interface between the user and computer hardware. Examples include Linux, Windows, macOS, Android, and the indigenous Indian OS 'BharOS'.

Understanding network topologies, transmission media, mobile generation standards, and satellite communication.

• Network Types: Classified by geographical spread into PAN (Personal), LAN (Local), MAN (Metropolitan), and WAN (Wide Area, e.g., Internet).
• Optical Fiber Communication: Works on the principle of Total Internal Reflection (TIR) of light waves through glass or plastic cores, offering high data rates and immunity to electromagnetic interference.
• Mobile Generations (2G to 5G): 2G introduced digital voice; 3G enabled mobile broadband; 4G brought LTE and high-speed packet data; 5G utilizes millimeter waves and massive MIMO for ultra-low latency.
• IP Addressing: IPv4 uses 32-bit addresses (e.g., 192.168.1.1) written in decimal, while IPv6 uses 128-bit addresses written in hexadecimal to overcome address exhaustion.

Essential communication protocols, web standards, cyber threats, and defensive mechanisms.

• TCP/IP Suite: Transmission Control Protocol ensures reliable, ordered delivery of data packets, while Internet Protocol handles packet routing across interconnected networks.
• World Wide Web (WWW): Invented by Tim Berners-Lee in 1989. It uses HTTP/HTTPS protocols and HTML (HyperText Markup Language) to render web pages via web browsers.
• Malware Types: Viruses replicate by attaching to host programs; Worms spread independently across networks; Ransomware encrypts user data demanding payment for decryption.
• CERT-In: Indian Computer Emergency Response Team is the national nodal agency for responding to cyber security incidents under the Ministry of Electronics and Information Technology.

Cloud computing, Artificial Intelligence, Blockchain, and key Indian e-governance infrastructure.

• Cloud Computing Models: Divided into IaaS (Infrastructure as a Service), PaaS (Platform as a Service), and SaaS (Software as a Service). Deployment models include Public, Private, and Hybrid clouds.
• Artificial Intelligence & Machine Learning: AI enables machines to mimic human intelligence. Generative AI models (like LLMs) process natural language, while Machine Learning allows systems to learn from data without explicit programming.
• DigiLocker: A flagship initiative under Digital India corporation providing a secure cloud-based platform for storage, issuance, and verification of official documents and certificates.
• Supercomputing in India: National Supercomputing Mission (NSM) aims to build supercomputers like Param Siddhi, Mihir, and Pratyush, boosting scientific research and weather forecasting capabilities.