RSSB Computer Instructor key terms

A design in which program instructions and data sit together in the same memory, and a single processor fetches, decodes and executes them one step at a time over a shared bus.

The repeating sequence a CPU performs for each instruction: fetch it from memory, decode its operation, execute it using the ALU or control unit, and store any result back.

Very small, very fast storage locations built inside the processor that hold the current instruction, addresses and operands during execution, far quicker to reach than main memory.

A small high-speed memory placed between the processor and main RAM that keeps recently or frequently used data, reducing the average time needed to fetch instructions and operands.

The layered arrangement of storage from fast, small and costly registers and cache down to slow, large and cheap disk and tape, each level trading speed against capacity and price.

A process is a running program with its own memory space; a thread is a lighter unit of execution inside that process, sharing its memory with sibling threads and switching more cheaply.

Saving the state of one running process or thread and restoring another so the CPU can move between them, an overhead activity that does no useful user work itself.

A standstill where each of several processes holds a resource another needs and waits forever, typically requiring mutual exclusion, hold-and-wait, no preemption and circular wait together.

A technique giving each program an apparent large contiguous address space, with pages moved between RAM and disk, so programs can exceed physical memory and stay isolated.

Dividing memory into fixed-size blocks called pages and frames so that a program's pages can be placed in any free frames, avoiding external fragmentation at the cost of page tables.

A collapse in performance when a system spends most of its time swapping pages in and out instead of executing instructions, usually because too many processes compete for too little RAM.

A preemptive CPU scheduling policy that gives each ready process a fixed time slice in turn, cycling through the queue so no process waits indefinitely and response time stays predictable.

A seven-layer conceptual framework for network communication, from physical signalling up through data link, network, transport, session, presentation and application, used to describe and compare protocols.

The practical four-layer suite actually used on the Internet: network access, internet, transport and application, with IP handling addressing and routing and TCP or UDP carrying data.

Wrapping data in successive protocol headers as it moves down the layers, each layer adding its own control information, which the receiving side strips off in reverse order.

A 32-bit pattern of ones then zeros that separates the network portion of an IPv4 address from the host portion, letting devices decide whether a destination is local or must be routed.

The process of choosing the path a packet takes across interconnected networks, using routing tables or dynamic protocols that learn reachable destinations and pick the best next hop.

Organizing relational tables so each fact is stored once, removing redundancy and update anomalies by splitting relations according to functional dependencies and keys.

A column or minimal set of columns whose values uniquely identify every row in a table and can never be null, serving as the main reference point for the relation.

An attribute in one table whose values must match a primary key value in another table, enforcing referential integrity between related relations.

The four guarantees of a reliable transaction: atomicity means all or nothing, consistency keeps rules intact, isolation hides uncommitted changes, and durability survives a crash.

A measure of how an algorithm's running time grows with input size, usually written in big-O notation such as O(n log n), ignoring constant factors and machine details.

Linear data structures with restricted access: a stack adds and removes at one end in last-in-first-out order, while a queue adds at the rear and removes from the front, first-in-first-out.

A binary tree in which every node's left subtree holds smaller keys and right subtree larger keys, allowing search, insertion and deletion in time proportional to tree height.

The structured phases of building software: requirements gathering, analysis, design, coding, testing, deployment and maintenance, organized differently by models such as waterfall or iterative.

An iterative approach delivering working software in short increments, with close customer collaboration, adaptive planning and continuous feedback preferred over a single fixed up-front specification.

Checking individual functions or modules in isolation against expected outputs, usually automated, to catch defects early before components are integrated together.

Transforming readable plaintext into unreadable ciphertext using a key and algorithm, so that only parties holding the correct key can recover the original message.

A cryptographic value attached to a message that proves its origin and integrity, created with the sender's private key and verified by anyone using the matching public key.

A social-engineering attack that impersonates a trusted entity through fake email, messages or websites to trick users into revealing passwords, card numbers or other sensitive data.

A basic digital circuit element such as AND, OR, NOT, NAND or XOR that produces an output determined entirely by its current binary inputs according to a truth table.

A grid arrangement of truth-table cells used to simplify Boolean expressions visually by grouping adjacent ones into the largest possible power-of-two blocks.

A bistable storage circuit that holds one bit and changes state on a clock edge or input signal, forming the building block of registers and sequential logic.

Rajasthan's three-tier rural local-government system of gram panchayat, panchayat samiti and zila parishad, introduced nationwide following the 73rd Constitutional Amendment.

A major irrigation canal in western Rajasthan, begun in the 1950s, that carries water from the Harike barrage on the Sutlej-Beas system to districts such as Jaisalmer and Barmer.

An approach that places students' needs, prior knowledge and active participation at the centre of planning, with the teacher acting as facilitator rather than sole source of information.

Ongoing, low-stakes checking of understanding during teaching, such as questioning or quizzes, used to adjust instruction and give feedback rather than to assign final grades.

The Hindi grammatical process in which the final sound of one word combines with the initial sound of the next to form a single joined word, as in विद्या plus आलय becoming विद्यालय.