CAC, or customer acquisition cost, is the average sales and marketing spend needed to win one new paying customer in a given…
A CPU cache is small, very fast memory inside the processor that keeps recently used data and instructions close to the cores…
Cache hit ratio is the share of requests a CDN or cache answers from stored copies instead of the origin, a key…
Caddy is an open-source web server and reverse proxy written in Go, known for automatic HTTPS with certificate management built into its…
The calotype is the early paper negative process patented in 1841 that made multiple positive prints from one camera exposure possible.
A camcorder is a video camera that combines a lens, image sensor and recorder in one handheld body, designed for continuous video…
Camera calibration estimates a camera's intrinsic, distortion and extrinsic parameters so a robot can turn image pixels into accurate geometric measurements.
A camera color profile in photography translates a sensor's raw RGB values into standard colors, defining hue, saturation and tone after white…
Camera movement in cinematography is any change in camera position or orientation during a shot, used to reveal space, follow action and…
A camera obscura is a darkened chamber in which light passing through a small opening projects an inverted image, the optical ancestor…
Canary deployment is a DevOps release strategy that sends a small share of traffic to a new version and widens it only…
A canonical URL is the preferred address of a page that search engines index and rank when the same content is reachable…
The Canvas API is a browser interface for drawing 2D graphics, text and images pixel by pixel into an HTML canvas element…
A capture card is a peripheral that receives a video signal from a console, camera or computer and converts it into a…
Card-not-present fraud is the use of stolen or fabricated card details to pay online, by phone or by mail, where the physical…
Card sorting is a UX design research method in which participants group content items into categories to reveal how users expect information…
Card testing is a fraud attack in which criminals run many small payments through a store to find out which stolen card…
Cardinality in data modeling defines how many instances of one entity can relate to instances of another, such as one-to-many or many-to-many.
Carrier aggregation combines several radio channels, often in different frequency bands, into one wider data pipe for a single LTE or 5G…
Cart abandonment is when online shoppers add products to the cart but leave without buying, a key conversion metric for every e-commerce…
CAT6 is a twisted-pair copper cabling category rated to 250 MHz, used for Gigabit Ethernet up to 100 m and 10 Gigabit…
A CCD is an image sensor that moves collected charge across the chip to a single output amplifier, valued in photography for…
CCS (Combined Charging System) is the charging standard that combines AC and high-power DC charging in one vehicle inlet, with CCS1 and…
A ccTLD is a country code top-level domain such as .de or .jp, a two-letter domain name ending reserved for a country…
CD in DevOps means continuous delivery or continuous deployment, the practice of keeping every change releasable through an automated pipeline.
A CDN is a geographically distributed network of caching servers that delivers web content from locations close to users to cut latency…
A Certificate Authority is a trusted organization that verifies identities and issues signed digital certificates binding public keys to domain names.
A certificate chain is the ordered sequence of X.509 certificates that links a server certificate through intermediates to a trusted root authority.
cgroups, or Linux control groups, organize processes into a hierarchy and limit, account for and isolate their CPU, memory and I/O usage.
CHAdeMO is a Japanese DC fast charging standard for electric vehicles, defining a dedicated connector, CAN-based communication and early bidirectional charging.
Change data capture (CDC) detects inserts, updates and deletes in a source database and delivers them as a stream of change events…
A chargeback is a forced reversal of a card payment that the cardholder's bank initiates through the card network after a dispute…
A charging curve shows how an electric vehicle's charging power changes with battery state of charge, and it decides real DC fast…
A charging network is a group of electric vehicle charging stations run under one operator or brand, with shared access, pricing and…
Chat history retention defines how long an AI assistant provider stores conversations, in which copies, for what purposes and how deletion really…
Checkout is the final stage of an e-commerce purchase, where the buyer confirms items, enters delivery and payment details and places the…
Checkout optimization is the systematic improvement of an online store's checkout flow to raise completed orders by removing friction, doubt and errors.
Checkpointing saves the progress and state of an automated workflow or job at defined points, so it can resume after a failure…
A chiplet is a small silicon die designed to be combined with other dies in one package, so that a large processor…
A chipset is the motherboard logic that connects the processor to storage, USB, networking and expansion slots, defining a board's features and…
chmod is the Linux command that changes file mode bits, setting read, write and execute permissions for the owner, group and others…
Chorus is an audio effect that mixes a signal with slightly delayed, pitch-modulated copies of itself, making one voice or instrument sound…
chown is the Linux command that changes the user and group owner of files and directories, which decides whose permission bits apply…
Chroma key is a compositing technique that removes a uniform green or blue background by color so a subject can be placed…
Chroma subsampling reduces the resolution of color information in video while keeping full brightness detail, saving bandwidth with little visible loss.
Chromatic aberration is a lens fault in which different wavelengths focus at different points, causing colored fringes along high-contrast edges.
Chromatic noise in photography is random color variation between pixels, seen as colored speckles or blotches in shadows and high-ISO images.
Chromium is the open-source browser project behind Chrome, Edge, Opera and Brave, built on the Blink rendering engine and the V8 JavaScript…
Chunking in retrieval systems splits documents into smaller passages that can be embedded, indexed and retrieved as context for a language model.
Churn rate is the share of customers or recurring revenue a subscription business loses in a period, a core SaaS metric for…