WBBSE Madhyamik Computer Application (Optional) key terms

The smallest unit of digital data, holding exactly one of two values, 0 or 1. Groups of bits are combined to represent larger numbers, characters, and instructions inside a computer.

A group of eight bits treated as one unit. It is the standard measure of storage size and can hold one ASCII character or a small integer value.

A base-2 positional number system that uses only the digits 0 and 1. Each position represents a power of two, and computers use it because circuits have two stable states.

The process of changing a base-10 number into base-2 by repeatedly dividing by 2 and recording remainders, then reading them upward. For example, 13 becomes 1101.

A base-8 system using digits 0 to 7. Three binary bits correspond to one octal digit, so it offers a compact shorthand for binary values.

A base-16 system using digits 0 to 9 and letters A to F. Four binary bits map to one hex digit, making it a convenient notation for memory addresses and colour codes.

American Standard Code for Information Interchange, a 7-bit character code assigning numeric values to letters, digits, and symbols. For example, uppercase A is 65.

A universal character-encoding standard that assigns a unique code point to characters of most of the world's writing systems, overcoming the limited range of older single-byte codes.

A rule set that maps characters to the numeric codes stored by a computer. Different encodings can produce different byte sequences for the same visible text.

The main processor that fetches, decodes, and executes program instructions. It contains the arithmetic logic unit and control unit and coordinates all other hardware components.

Volatile primary memory that holds programs and data currently in use. Its contents are lost when power is switched off, and it can be read and written quickly.

Non-volatile memory whose contents are retained without power and normally cannot be changed by ordinary programs. It often stores firmware such as the boot instructions.

A small, very fast memory placed close to the CPU that stores recently used instructions and data, reducing the average time needed to access main memory.

Software permanently stored in read-only or flash memory on a device, providing low-level control of that hardware. It usually stays unchanged during normal operation.

System software that manages hardware resources, files, and processes, and provides services so application programs can run without dealing directly with the hardware.

A translator that converts an entire high-level language program into machine code before execution, reporting errors for the whole program at once.

A translator that reads a high-level program statement by statement and executes each one immediately, stopping at the first error it meets.

The human-readable program text written by a programmer in a high-level language, which must be translated before the computer can execute it.

A finite, ordered set of unambiguous steps that solves a problem or completes a task. Every step must be clear, and the process must terminate after a limited number of operations.

A diagram that represents an algorithm using standard symbols such as ovals for start and end, parallelograms for input and output, rectangles for processing, and diamonds for decisions.

An informal, structured description of an algorithm using plain-language statements and programming-like keywords, without the strict grammar of any real language.

A named storage location whose value can change while a program runs. Each variable has a data type that determines what values it may hold.

A named value that is fixed when the program is written and cannot be altered during execution, often used for values such as the value of pi.

A classification that specifies which kind of values a variable may store, such as integer, real, character, or string, and which operations are allowed on them.

The explicit conversion of a value from one data type to another, for example turning an integer into a real number or a character into its numeric code.

The fixed order in which operators in an expression are evaluated, so that multiplication and division are performed before addition and subtraction unless brackets change the order.

An operator such as less than, greater than, or equal to that compares two values and produces a true or false result, commonly used to control decisions and loops.

An operator such as AND, OR, or NOT that combines or reverses true/false conditions, allowing compound tests in decision statements and loop conditions.

A control structure that executes one block of statements or another depending on whether a tested condition is true, directing the flow of the program.

A control structure that repeats a block of statements while a condition holds or for a fixed number of times, avoiding the need to write repeated code.

A loop whose terminating condition never becomes false, so the repetition continues without end and the program fails to finish normally.

A collection of elements of the same data type stored in consecutive positions and accessed by an index, usually starting from zero in many languages.

A number that identifies the position of an element within an array or string, used to read or change that element directly.

A sequence of characters treated as a single value, such as a name or sentence, which can be searched, joined, compared, or cut into parts.

A mistake in the grammar of a program, such as a missing bracket or misspelled keyword, which prevents the translator from producing executable code.

A fault in the reasoning of a program that lets it run but produce wrong results, often caused by an incorrect formula or a reversed condition.

The process of locating and correcting errors in a program by reading the code, tracing values, and testing with sample inputs until the output is correct.

A unique numeric label assigned to a device on a network so that data packets can be addressed and delivered to the correct destination.

Uniform Resource Locator, the address typed into a browser that identifies the protocol, server, and path of a resource on the World Wide Web.

An agreed set of rules that governs how data is formatted, transmitted, and received between devices, allowing different systems to communicate reliably.

A deception in which attackers send fake messages or links that imitate trusted organisations to trick users into revealing passwords or financial details.

Any software written to harm or exploit a computer system, including viruses, worms, and spyware that damage files or steal information.

A password that is long and mixes upper and lower case letters, digits, and symbols, avoids personal details, and is not reused across accounts.

A login method requiring two independent proofs of identity, such as a password plus a one-time code sent to a phone, so a stolen password alone is not enough.

A program that scans files and running processes for known patterns of malicious code, quarantines threats, and updates its detection data regularly.

A hardware or software filter that inspects network traffic and blocks connections that do not match allowed rules, protecting a device or network from intrusion.

The branch of computing concerned with systems that perform tasks associated with human intelligence, such as learning from data, recognising patterns, and making decisions.

A subfield of artificial intelligence in which programs improve their performance on a task by learning patterns from data rather than following only hand-written rules.

The delivery of computing services such as storage, processing, and software over the Internet from remote data centres, instead of from local machines.