Technology – MCQ – GK Questions

Primary Key is a column or set of columns that uniquely identifies each row in a table. It cannot contain NULL values and must be unique. Foreign keys establish relationships between tables, while candidate keys are potential primary keys.

Switch is a networking device that connects devices within a LAN and uses MAC addresses to forward data frames only to the intended recipient port. Unlike hubs that broadcast to all ports, switches improve network efficiency and security.

DDoS (Distributed Denial of Service) attack uses multiple compromised systems to flood a target server with traffic, exhausting resources and making services unavailable. Mitigation includes traffic filtering, rate limiting, and using DDoS protection services.

SMS (Short Message Service) is a text messaging service component of most telephone, internet, and mobile device systems. It uses standardized communication protocols to exchange short text messages (up to 160 characters) between devices.

Registers are the fastest memory type, located inside the CPU, used for immediate data processing. Cache is next fastest (L1/L2/L3), followed by RAM, then storage devices (SSD/HDD). Speed hierarchy: Registers > Cache > RAM > SSD > HDD.

IoT (Internet of Things) refers to network of physical devices embedded with sensors, software, and connectivity to collect and exchange data. Applications include smart homes, industrial automation, healthcare monitoring, and smart cities.

Stack is a linear data structure that follows LIFO principle - the last element added is the first to be removed. Operations include push (add) and pop (remove). Used in function call management, expression evaluation, and undo mechanisms.

BharatNet (formerly National Optical Fibre Network) aims to connect all 2.5 lakh gram panchayats with high-speed optical fiber. It is one of the world's largest rural connectivity projects, enabling delivery of e-governance, education, and healthcare services.

2G (specifically GPRS/EDGE enhancements) introduced packet-switched data transmission, enabling always-on internet access and efficient data usage. 1G was analog voice only; 3G improved data speeds; 4G introduced all-IP architecture with higher bandwidth.

HTTPS indicates that communication between browser and website is encrypted using SSL/TLS protocols. This protects data from eavesdropping and tampering. Users should look for the padlock icon and 'https://' when entering sensitive information online.

Quantum Computing uses qubits that can exist in superposition (0 and 1 simultaneously) and entanglement (correlated states) to solve certain problems exponentially faster than classical computers, with applications in cryptography, drug discovery, and optimization.

Scanner is an input device that captures images, text, or objects and converts them into digital format. Monitor, printer, and speaker are output devices that display or present processed information to the user.

Mangalyaan (Mars Orbiter Mission), launched in 2013, made India the first Asian nation and fourth space agency globally to reach Mars orbit. It was completed at a cost of just $74 million, making it one of the least expensive Mars missions.

SELECT is the SQL command used to query and retrieve data from one or more tables. INSERT adds new records, UPDATE modifies existing records, and DELETE removes records. SELECT is the most frequently used command in database operations.

AES (Advanced Encryption Standard) is a symmetric algorithm using the same key for encryption and decryption. RSA, ECC, and Diffie-Hellman are asymmetric algorithms using public-private key pairs. AES is widely used for securing sensitive data.

DNS (Domain Name System) translates human-readable domain names into numerical IP addresses that computers use to identify each other on the network. Without DNS, users would need to remember IP addresses like 142.250.189.206.

PSLV (Polar Satellite Launch Vehicle) is called ISRO's workhorse due to its reliability in launching earth observation and remote sensing satellites into polar sun-synchronous orbits. It has successfully launched Chandrayaan-1 and Mangalyaan.

RAM (Random Access Memory) is volatile memory used for temporary storage of data and machine code currently being used. It loses all data when power is switched off, unlike ROM or hard disk which are non-volatile.