HTML glossary

Shortened form of a term marked up with `abbr`, often expanded through a `title` attribute.

Interface pattern that lets the user expand and collapse sections of content to reduce visual noise.

Alternative description provided through the `alt` attribute of an image so its meaning is still available without sight or without the file loading.

HTML link element written with `a`, often used with `href` to create navigation targets.

Accessibility attribute system that helps describe custom interface behavior to assistive technologies when native HTML is not enough.

Extra information written inside an opening HTML tag to define details such as destination, type or description.

HTML media element used to embed playable sound content in a page.

The part of an HTML document that contains the visible and interactive content of the page.

Preferred URL declared for a page when multiple similar URLs might exist.

A group of user-focused metrics that measure loading, visual stability and interaction quality.

Element that provides suggested values for an input without forcing the user into a closed selection.

List created with `dl` to pair terms with their explanations.

Declaration that tells the browser to interpret the document using modern HTML standards mode.

A complete HTML unit made of a tag and, when applicable, its content and closing tag.

Form element used to group related controls into one semantic block.

HTML structure used to collect and submit data entered by the user.

Part of web development that runs in the browser and includes structure, styling and user-facing behavior.

Attribute that can be used on many HTML elements, such as `id`, `class`, `title`, `hidden` or `data-*`.

The document section that stores metadata such as title, charset, viewport settings and linked resources.

A structural title element such as `h1` to `h6` that defines hierarchy inside the page.

HyperText Markup Language. Markup language used to structure content on the web.

HTML element used to embed another browsing context, such as a video player or external page.

Form control element used to capture user data such as text, email, numbers or passwords.

Inline semantic representation of a key or shortcut, usually marked up with the `kbd` element.

Text element associated with a form control so users know what information the field expects.

Caption-like label that names the purpose of a `fieldset` group.

Navigational connection created in HTML so users can move to another page, resource or section.

Structured group of related items represented in HTML with list elements such as `ul`, `ol` or `dl`.

Metadata summary that describes the page for search and preview contexts.

Information about the document that helps browsers, search engines and tools understand how the page should be handled.

Element that represents a value within a known range, such as quality, risk or battery level.

List created with `ol` when the sequence of the items matters.

A block of text represented with the `p` element, usually used for one coherent idea or reading unit.

Element that represents how much of a task has been completed, usually marked up with `progress`.

A script loading strategy that downloads in parallel and runs as soon as it is ready, without preserving order.

A script loading strategy that downloads in parallel but runs after HTML parsing finishes, preserving order.

Use of HTML elements according to their meaning and role instead of choosing them only for appearance.

Machine-readable metadata, often provided with JSON-LD, that helps describe what the page content represents.

HTML structure used to represent data organized in rows and columns.

Short label that explains what a table represents as a whole.

Header cell marked up with `th` to describe a row or column in a table.

The markup syntax used to define an HTML element, usually with an opening form and often a closing form.

List created with `ul` when the order of the items does not matter.

HTML media element used to embed playable video content in a page.