The SEO glossary.Plain-English definitions, no fluff.

Text in an image's `alt` attribute that describes the image. Used by screen readers and by search engines that cannot see the picture.

A hyperlink on one website that points at another. Search engines treat backlinks as one signal of how the wider web vouches for a page.

An HTML element that tells search engines which URL is the master copy when the same or similar content exists at multiple addresses.

A set of three Google metrics that measure real-world page experience: loading speed, interactivity and visual stability.

The number of URLs a search engine crawler will fetch and the rate at which it fetches them on a given site.

Google's framework for assessing content quality across four lenses: Experience, Expertise, Authoritativeness and Trust.

An HTML attribute or sitemap tag that tells search engines which language and region a page is intended for, so the right version is shown to the right user.

The process by which a search engine analyses a fetched page and stores information about it so the page can later be returned in search results.

A short HTML attribute summarising a page, often used by search engines as the snippet shown beneath a result's title.

A plain-text file at the root of a domain that tells crawlers which paths they may or may not request.

Structured data added to a page that describes its content to search engines in a machine-readable format.

The underlying goal a person has when entering a query into a search engine — what they actually want to find, do, or know.

The page a search engine returns in response to a query, including the list of results and any features such as ads, knowledge panels and rich snippets.

A file, usually XML, that lists URLs on a site so search engines can discover and crawl them more efficiently.

A permanent redirect — an HTTP 301 status code telling clients and search engines that a URL has moved permanently to a new location.