Web glossary

A 301 redirect is a permanent forwarding instruction that sends a browser from an old web address to a new one and tells search engines that the page has moved.

Alt text is a text alternative that communicates an image's relevant information or function when someone cannot see it, with wording chosen for the image's purpose in that particular page.

An API, or application programming interface, defines how software can use another software component's capabilities. It specifies available operations and the information those operations accept or return.

A canonical URL is the address selected to represent a page among duplicate or very similar versions; a website can suggest its preferred address, while search engines make their own selection.

A CMS, or content management system, is software for creating, organizing, editing and publishing content. It gives the people maintaining a website a place to manage information, with editing controls that depend on how the system is set up.

Conditional logic uses an answer or another condition to decide what happens next, such as showing a relevant follow-up question only to the people who need to answer it.

A content model defines the kinds of information a website manages, the fields each kind needs and the relationships between them. It describes how content is organized, so repeated information can be maintained consistently and used in different places.

CSV, short for comma-separated values, is a plain-text way to exchange a table of records between tools, using separators and quoting rules to keep the fields in each record distinct.

DNS, the Domain Name System, is the system that lets applications look up information associated with a domain name, including where to connect for a website and which servers receive its email.

A domain name is a readable name, such as example.com, used to identify a location on the internet. DNS connects the name to services such as a website or email; registering it does not supply those services by itself.

Form validation checks whether entered information follows a form's rules, such as required answers, permitted formats and allowed ranges. It identifies entries that need correction before the receiving system accepts them.

An HTTP status code is a three-digit number in a server's response that describes the outcome of a request. It can indicate success, a redirect or an error, independently of the words and design shown on the page.

Image compression represents image data using fewer bytes, with a choice between preserving that data exactly and discarding some detail to reduce the file size further for a particular use.

JSON, short for JavaScript Object Notation, is a text format for exchanging structured data, such as a saved form plan, an application response or a collection of product details.

A meta description is a short page summary stored in HTML metadata that search engines may use in a result's descriptive text, although the displayed snippet can come from other page content.

Open Graph is a metadata format that describes a web page to services displaying shared links, giving them a title, page type, image and identifying URL to work with.

Responsive design is an approach to building websites that adapt their layout, media and controls to the available space, so the same content stays usable across different screen sizes and browser settings.

A staging site is a review version of a website used to check changes before they reach the production site visitors normally use. Its data, connected services and access controls depend on how the review environment is configured.

Structured data is information expressed in a consistent, machine-readable format; on a website, it can label facts about an organization, article, service, or other content so software can interpret their meaning.

UTM parameters are labels added to a destination URL so a compatible analytics setup can identify the promotion associated with an incoming visit and organize collected traffic into useful reporting groups.

Web hosting is the service that stores and serves a website's files or runs its application so visitors can reach it online. It provides the working destination behind a web address, while domain registration and website maintenance are separate responsibilities.

A webhook is a notification sent from one application to another when a chosen event happens. It delivers event data to a configured web address so the receiving application can respond.

An XML sitemap is a structured file listing website URLs for search engines, with optional information such as meaningful update dates, to help them discover the pages the site wants considered for indexing.