NIELIT BCC key terms

The combined use of computers, telecommunications networks, and software to create, store, process, and exchange information. It covers hardware, applications, and services used in homes, offices, and public services.

Transmission of signals such as voice, data, or video over a distance using electrical, radio, or optical media. Mobile networks, landlines, and internet backbones all rely on it.

The maximum rate at which data can be carried over a communication channel, usually measured in bits per second. Higher bandwidth allows more simultaneous traffic but does not by itself guarantee low delay.

The time delay between sending a request and receiving the first response, measured in milliseconds. It affects the responsiveness of video calls and online games more than raw bandwidth does.

The amount of data actually transferred successfully in a given period, often lower than the nominal bandwidth because of overhead, congestion, or errors. It reflects real-world performance rather than theoretical capacity.

A device that converts digital signals from a computer into a form suitable for a transmission line and back again. It connects a subscriber's premises to an ISP over telephone, cable, or fibre links.

A networking device that forwards data packets between different networks by choosing a path based on destination addresses. Home routers typically combine routing, switching, and wireless access functions.

A network covering a limited area such as a room, building, or campus, in which devices communicate at high speed. It is usually owned and managed by a single organisation.

A numeric label assigned to each device on a network so that data can be delivered to the correct destination. IPv4 addresses are 32 bits; IPv6 addresses are 128 bits.

A hierarchical naming service that translates human-readable domain names into numeric IP addresses. Without it, users would have to remember numeric addresses for every website.

A company that provides subscribers with access to the internet for a fee, often bundling email, hosting, or television services. It assigns addresses and routes customer traffic to the wider network.

The address used to locate a resource on the web, typically containing a scheme, a host name, and a path. For example, https indicates the protocol while the remaining parts identify the server and page.

An encrypted version of the web transfer protocol that protects data exchanged between browser and server. It uses certificates to authenticate the site and is indicated by a padlock in the address bar.

Hardware or software that inspects network traffic and blocks or permits it according to configured rules. It helps protect a device or network from unauthorised access and malicious traffic.

An electronic document issued by a trusted authority that binds a public key to an identity such as a website owner. Browsers use it to verify authenticity and enable encrypted connections.

An electronic machine that accepts data, processes it according to stored instructions, stores results, and produces output. Its main parts are input, processing, storage, and output units.

The component that fetches, decodes, and executes program instructions, performing arithmetic and logical operations. Its speed is influenced by clock rate, core count, and cache size.

Volatile working memory that holds programs and data currently in use, allowing fast read and write access. Its contents are lost when power is removed, unlike permanent storage.

Non-volatile memory whose contents are retained without power and are normally read-only during operation. It often stores firmware such as the boot instructions used at start-up.

A small, very fast memory placed close to the processor that holds frequently used instructions and data. It reduces the average time needed to fetch information from main memory.

Software stored permanently on a hardware device that controls its basic operation and is rarely changed by users. Updating it can add features or fix security flaws.

System software that manages hardware resources, files, and processes, and provides services to application programs. It supplies the user interface and controls memory allocation and device access.

Programs designed to help users perform specific tasks such as word processing, accounting, or browsing the web. They depend on the operating system for access to hardware resources.

Small programs that maintain, protect, or optimise a computer system, for example disk cleanup, backup, or antivirus tools. They support the operating system rather than performing user work directly.

A software component that lets the operating system communicate with a particular hardware device. It translates general commands into instructions the specific device understands.

The method an operating system uses to name, store, organise, and retrieve files on a storage device. It defines directory structures, permissions, and how space is allocated.

The suffix after the final dot in a file name that indicates the file's format or associated program, such as .docx or .jpg. It helps the system choose which application opens the file.

Application software for creating, editing, formatting, and printing text documents. Typical features include spell checking, tables, styles, headers, and page layout control.

Application software that organises data in rows and columns of cells and recalculates formulas automatically when values change. It is widely used for budgets, lists, and charts.

An expression entered in a spreadsheet cell that begins with an equals sign and computes a result from values or cell references. It updates automatically when the referenced data changes.

A built-in spreadsheet routine such as SUM or AVERAGE that performs a calculation on supplied arguments and returns a value. Functions save time compared with writing long manual formulas.

Application software used to build slide shows combining text, images, charts, audio, and transitions for an audience. Slides can be projected, printed as handouts, or exported to other formats.

A service for sending and receiving digital messages over a network, with fields for recipient, subject, body, and attachments. Messages are stored on servers until the recipient retrieves them.

A file sent along with an email message, such as a document, image, or archive. Providers usually limit attachment size, so large files are often shared through links instead.

Delivery of computing services such as storage, software, and processing power over the internet on demand. Users pay for what they use and avoid maintaining physical servers themselves.

A service that keeps files on remote servers accessible over the internet from multiple devices. It supports backup, sharing, and synchronisation but depends on network availability.

A copy of data kept separately so that it can be restored if the original is lost, corrupted, or damaged. Effective backup schemes are regular, verified, and stored off the main device.

Any software written to harm, disrupt, or gain unauthorised access to a system, including viruses, worms, trojans, and ransomware. Protection relies on updates, cautious behaviour, and security tools.

A deceptive attempt to obtain sensitive information such as passwords or card numbers by impersonating a trusted entity through email, messages, or fake websites. Suspicious links and urgency are common warning signs.

Unsolicited bulk messages sent indiscriminately, usually for advertising or fraud. Filters and reporting help reduce it, and users should avoid replying or opening unknown attachments.

The ability to find, evaluate, create, and communicate information safely using digital devices and services. It includes practical skills, critical judgement of online content, and responsible behaviour.