Technology

Computer recycling: recovery, refurbishment, and safe e-waste management Computer recycling Overview of computer recycling: processes (refurbish, harvest, material recovery), hazards, history, uses, and best practices for safe disposal and data protection.

Computer security: principles, threats, and defenses Computer security Comprehensive overview of computer security: goals (confidentiality, integrity, availability), common threats, defensive controls, secure development, risk management, incident res…

Computer speakers Computer speaker Devices that reproduce audio from a computer; types, components, connectivity, history, uses, and how they differ from other speaker systems.

Computer terminal A computer terminal is a device or program used to enter and display text-based information on a host computer. It covers historical hardware terminals and modern software emulator…

Computer virus A computer virus is a type of malicious software that replicates by inserting copies of itself into other programs or files. This article explains how viruses work, how they spread…

Computer worm: self-replicating malware that spreads across networks Computer worm A computer worm is self-replicating malware that propagates across networks or removable media without attaching to other files; this article explains how they work, history, impac…

Computer-aided manufacturing (CAM) Computer-aided manufacturing Computer-aided manufacturing (CAM) uses computer systems to plan, control and automate manufacturing equipment, improving precision, efficiency and repeatability across many indust…

Computer-generated imagery (CGI): techniques, history, and applications Computer-generated imagery Overview of computer-generated imagery: how it is made, historical development, core techniques, common uses in film, games, advertising and science, and distinctions from related…

Computing platform: definition, components, types and uses Computing platform A computing platform is the combination of hardware, firmware, operating system and runtime layers that support running applications. This article explains its parts, history, type…

Concurrency (computer science) Concurrency is the structuring and execution of overlapping computational tasks to improve responsiveness, resource use, or modularity; distinct from parallelism and requiring coor…

Consumer electronics: overview, categories, history, and issues Consumer electronics Electronic devices for everyday personal and household use — categories, development, typical features, applications, and environmental and design challenges.

Consumer Electronics Show (CES): Annual technology trade event Consumer Electronics Show CES is a major annual trade show for consumer technology held each January in Las Vegas, where companies unveil products, host keynotes, and shape industry trends.

Contactless smart card A plastic card with an embedded chip and antenna that exchanges data with a reader by short-range radio; used for payments, transit, ID, access control and secure data storage.

Content Scramble System (CSS) — DVD encryption and its legacy Content Scramble System Content Scramble System (CSS) is the encryption and copy-protection scheme introduced for commercial DVDs in 1996. It was cryptographically weak and publicly broken, shaping DRM de…

Context (computing): the execution state of processes, threads and interrupts Context (computing) In computing, a task context is the set of processor and system state that must be saved to pause and later resume a process, thread or interrupt handler without loss of execution…

Context switch (computing) Context switch Switching the saved execution state of a processor so multiple tasks share CPU time; covers what is saved, when and why it happens, performance costs, hardware support and practica…

Contiki: lightweight operating system for networked embedded systems Contiki Contiki is a small, open-source operating system designed for networked, resource-constrained devices and embedded systems, notable for its tiny memory footprint and networking sup…

Control unit (computer CPU) Control unit Component of a CPU that decodes instructions and issues timing and control signals to coordinate the ALU, registers, memory and I/O; may be hardwired or microprogrammed.

Coordinated Universal Time (UTC) Coordinated Universal Time Coordinated Universal Time (UTC) is the global time standard used for clocks, navigation, communication and timekeeping; it is atomic-based and kept close to Earth's rotation with…

Copy-on-write (COW) — optimization for memory, storage, and data structures Copy-on-write Copy-on-write delays duplicating shared resources until a write occurs, saving memory and I/O. Widely used in operating systems, file systems, containers, and some programming libr…

Corkscrew: design, types, history and how to open a bottle Corkscrew Tool used to remove corks from wine bottles; covers parts, common styles, use technique, history, maintenance, and related developments such as screw caps and synthetic corks.

CornerShot: weapon accessory for firing and observing around corners CornerShot CornerShot is a tactical weapon system that lets an operator view and fire around obstacles without exposing their body. Used by police and special forces, it combines a hinged fra…

Cotton gin — machine for separating cotton fibers from seeds Cotton gin A cotton gin is a machine that separates cotton fibers from seeds. It transformed cotton processing, increased textile raw material supply, and had major economic and social conseq…

Crash (computing) A computing crash is an abrupt stop or malfunction of software or an operating system, caused by bugs, hardware faults, drivers, resource errors or security issues; this article ex…

Crash test dummy (Anthropomorphic Test Device) Crash Test Dummy An anthropomorphic test device (ATD), commonly called a crash test dummy, is an instrumented mannequin used to evaluate human injury risk and vehicle safety in simulated impacts.

Credit card: definition, components, history, uses and consumer issues Credit card Comprehensive overview of credit cards: what they are, how they work, common features, history, uses, security issues, and types of cards for consumers and merchants.

Cron: the Unix-like time-based job scheduler Cron Cron is a time-based job scheduler for Unix-like systems. It runs commands or scripts at specified times or intervals using per-user crontabs and supports special schedules and alt…

Cross-platform software: concepts, approaches, and practical trade-offs Cross-platform Overview of cross-platform software: definitions, development approaches, historical context, common tools, use cases and typical advantages and limitations faced by developers and…

Crosshair (reticle) Crosshair A crosshair or reticle is a visual aiming marker used in optical instruments and digital displays, appearing as intersecting lines, dots or patterns to indicate aim point, assist r…

Crowbar: design, history, uses and notable variants Crowbar Comprehensive overview of the crowbar — a handheld pry tool. Explains shapes, materials, historical origin, common uses, lever mechanics, safety considerations and notable types.

Cryptocurrency: digital money, technology, and uses Cryptocurrency An objective overview of cryptocurrencies: what they are, how they work, their history, common uses, risks, and major distinctions between types and systems.

Cryptographic protocol: purpose, components, history and applications Cryptographic protocol Overview of cryptographic protocols: definitions, core components (keys, authentication, encryption), common examples, threats, formal analysis, deployment considerations and best…

Cryptography: Principles, Methods, History, and Practical Uses Cryptography Overview of cryptography: core concepts (cipher, key, encryption), main methods (symmetric, public-key, hashing), historical development, real-world applications, and common securi…

CryptoLocker — file‑encrypting ransomware CryptoLocker CryptoLocker is a type of file‑encrypting ransomware first seen in 2013. It used public‑key cryptography to lock users’ files and demanded payment (often in Bitcoin) for a decrypti…

Crystal LED display technology Crystal LED Crystal LED is a direct‑emissive display approach (Sony's microLED) in which each RGB subpixel is an independent LED. It delivers high brightness, contrast, color and modular scala…

Crystal Radio (Crystal Set): Passive AM Receiver, History and Use Crystal radio Overview and history of the crystal radio: a simple, battery-free AM receiver, its components, operation, uses in education and wartime, limitations, and how it differs from modern…

Cursor (computer pointer and text caret): function, types, and usage Cursor A cursor indicates where input or actions will take effect on a screen. This article explains cursor types, appearance, behavior, controls, history, accessibility, and common disti…

Cyanotype: the historical blue photographic printing process Cyanotype Cyanotype is a contact photographic printing technique that yields characteristic Prussian-blue images. Invented in the 19th century, it has scientific, technical and artistic appl…

Cyberpunk (science fiction subgenre) Cyberpunk Cyberpunk is a science fiction subgenre that explores near-future worlds of advanced technology, cybernetics, corporate power and social decay. Covers origins, themes, major works,…

Cyborg: hybrid organisms combining biological and artificial systems Cyborg A cyborg (cybernetic organism) is a being with integrated organic and engineered parts. This article explains definitions, history, examples, distinctions, applications, and ethica…

D (programming language): overview, features, history, and uses D (programming language) D is a multi-paradigm, systems-level programming language designed to combine C/C++ performance with modern language safety and expressiveness for real-world software development.

Daemon (background computer process) Daemon (computer software) A daemon is a background computer program commonly found on Unix-like systems; this article explains what daemons are, how they run, typical uses, historical context, and how they…

Damn Small Linux (DSL): a tiny Live Linux for legacy x86 PCs Damn Small Linux Damn Small Linux (DSL) is a minimal 50 MB live Linux distribution for older x86 hardware, designed to fit on tiny media, run from RAM, and serve as a portable rescue or lightweight…

Dance Dance Revolution Dance Dance Revolution (DDR) is a Konami music-rhythm video game series where players step on a floor pad to match on-screen arrows in time with music, spanning arcades, consoles,…

Dancing with the Stars (video game) A 2007 licensed rhythm game based on the TV series, developed by Zoë Mode and published by Activision for Wii, later ported to Windows and mobile devices.

DarkBASIC DarkBASIC is a BASIC-derived programming environment designed to simplify Windows game development, offering built-in graphics and sound commands and a pathway to the more advanced…

Darlington transistor (Darlington pair) Darlington transistor A Darlington transistor is a compound arrangement of two bipolar transistors that provides a very high current gain. Used for switching and amplification, it has distinctive benefi…

Darwin (operating system) Darwin is Apple’s open-source Unix-like operating system kernel and userland foundation that forms the core of macOS and other Apple platforms, combining Mach, BSD and Apple-specif…