# HTML glossary

367 HTML terms, from Novice to Master. Start with the basics or jump to a level.

Updated: October 16, 2026

## Novice

- [<b>](https://www.ask-codey.com/glossary/b): The element that draws attention to text without adding importance or emphasis.
- [<body>](https://www.ask-codey.com/glossary/body): The element that contains the document content presented as the web page.
- [<br>](https://www.ask-codey.com/glossary/br): The element that creates a line break where the break is part of the content.
- [<div>](https://www.ask-codey.com/glossary/div): A generic container for flow content when no more meaningful element fits.
- [<em>](https://www.ask-codey.com/glossary/em): The element that marks stress emphasis that can change a sentence's meaning.
- [<figcaption>](https://www.ask-codey.com/glossary/figcaption): The element that provides a caption for its parent figure.
- [<figure>](https://www.ask-codey.com/glossary/figure): The element that groups self-contained content that may have a caption.
- [<head>](https://www.ask-codey.com/glossary/head-html): The element that contains document metadata rather than the page's main visible content.
- [<hr>](https://www.ask-codey.com/glossary/hr): The element that represents a thematic break between groups of content.
- [<html>](https://www.ask-codey.com/glossary/html): The root element that contains the head and body of an HTML document.
- [<i>](https://www.ask-codey.com/glossary/i): The element that marks text in an alternate voice or otherwise offset from normal prose.
- [<p>](https://www.ask-codey.com/glossary/p): The element that represents a paragraph.
- [<span>](https://www.ask-codey.com/glossary/span): A generic inline container for phrasing content when no more meaningful element fits.
- [<strong>](https://www.ask-codey.com/glossary/strong): The element that marks content as strongly important, serious, or urgent.
- [<title>](https://www.ask-codey.com/glossary/title): The element that gives a document the title shown in browser tabs and other interfaces.
- [Alternative text](https://www.ask-codey.com/glossary/alternative-text): Text that communicates an image's purpose when the image cannot or should not be viewed.
- [Anchor element](https://www.ask-codey.com/glossary/anchor-element): The a element, which creates a hyperlink when it has an href attribute.
- [Attribute](https://www.ask-codey.com/glossary/attribute-html): A name, sometimes paired with a value, that adds information or behavior to an element.
- [Attribute value](https://www.ask-codey.com/glossary/attribute-value): The data assigned to an HTML attribute.
- [Boolean attribute](https://www.ask-codey.com/glossary/boolean-attribute): An attribute whose presence means true and whose absence means false.
- [Character reference](https://www.ask-codey.com/glossary/character-reference): HTML syntax that represents a character using a named or numeric reference.
- [Child element](https://www.ask-codey.com/glossary/child-element): An element directly contained by another element.
- [class attribute](https://www.ask-codey.com/glossary/class-attribute-html): An attribute that contains one or more CSS classes.
- [Description details](https://www.ask-codey.com/glossary/description-details): A description, definition, or value associated with a term in a description list.
- [Description list](https://www.ask-codey.com/glossary/description-list): A list of terms or names paired with descriptions, definitions, or values.
- [Description term](https://www.ask-codey.com/glossary/description-term): A term or name being described inside a description list.
- [Document type declaration](https://www.ask-codey.com/glossary/document-type-declaration): The declaration at the start of a document that tells browsers to use modern HTML parsing.
- [Element](https://www.ask-codey.com/glossary/element): A part of an HTML document represented by a tag and, when allowed, its content.
- [Element content](https://www.ask-codey.com/glossary/element-content): The text and elements placed between an element's start and end tags.
- [End tag](https://www.ask-codey.com/glossary/end-tag): The tag that closes an HTML element, written with a slash before the tag name.
- [Fragment identifier](https://www.ask-codey.com/glossary/fragment-identifier): The portion of a URL that appears after the # symbol.
- [Global attribute](https://www.ask-codey.com/glossary/global-attribute): An attribute that can be used on every HTML element, subject to the attribute's rules.
- [Heading](https://www.ask-codey.com/glossary/heading): A title that introduces a page or section of content.
- [Heading element](https://www.ask-codey.com/glossary/heading-element): One of the h1 through h6 elements used to identify headings at different levels.
- [height attribute](https://www.ask-codey.com/glossary/height-attribute): An attribute that supplies an element's intended height in CSS pixels.
- [href](https://www.ask-codey.com/glossary/href): The attribute that supplies a hyperlink's destination URL.
- [HTML](https://www.ask-codey.com/glossary/html-html): The markup language used to give web content its structure and meaning.
- [HTML comment](https://www.ask-codey.com/glossary/html-comment): Text in HTML source that browsers do not display as page content.
- [HTML document](https://www.ask-codey.com/glossary/html-document): A text document containing HTML markup that a browser can parse into a web page.
- [HTML source](https://www.ask-codey.com/glossary/html-source): The original HTML text sent to or opened by a browser.
- [HTML validation](https://www.ask-codey.com/glossary/html-validation): Checking markup against HTML's conformance rules to find mistakes.
- [Hyperlink](https://www.ask-codey.com/glossary/hyperlink): A connection that a user can follow to another resource or location.
- [ID](https://www.ask-codey.com/glossary/id): A document-wide identifier assigned to a single element.
- [Image element](https://www.ask-codey.com/glossary/image-element): The img element, which embeds an image in a document.
- [Link element](https://www.ask-codey.com/glossary/link-element): This loads an external stylesheet.
- [List item](https://www.ask-codey.com/glossary/list-item): One entry inside an ordered, unordered, or menu list.
- [Markup language](https://www.ask-codey.com/glossary/markup-language): A language that adds labels to describe the content so that software can understand its structure and meaning.
- [Named character reference](https://www.ask-codey.com/glossary/named-character-reference): A character reference that uses a standard name, such as amp for an ampersand.
- [Nesting](https://www.ask-codey.com/glossary/nesting): Placing one HTML element inside another element.
- [Numeric character reference](https://www.ask-codey.com/glossary/numeric-character-reference): A character reference that identifies a Unicode character by number.
- [Ordered list](https://www.ask-codey.com/glossary/ordered-list): A list whose item order is meaningful.
- [Parent element](https://www.ask-codey.com/glossary/parent-element): An element that directly contains another element.
- [Sibling element](https://www.ask-codey.com/glossary/sibling-element): An element that shares the same parent as another element.
- [src](https://www.ask-codey.com/glossary/src): The attribute that gives the URL of an embedded resource such as an image or script.
- [Start tag](https://www.ask-codey.com/glossary/start-tag): The tag that opens an HTML element and can contain its attributes.
- [Style element](https://www.ask-codey.com/glossary/style-element): Embeds CSS directly in an HTML page.
- [Tag](https://www.ask-codey.com/glossary/tag-html): Markup enclosed in angle brackets that begins or ends an HTML element.
- [title attribute](https://www.ask-codey.com/glossary/title-attribute): A global attribute that provides advisory information about an element.
- [Unordered list](https://www.ask-codey.com/glossary/unordered-list): A list whose item order does not change the meaning.
- [Void element](https://www.ask-codey.com/glossary/void-element): An HTML element that cannot contain child content and has no end tag.
- [Whitespace](https://www.ask-codey.com/glossary/whitespace-software-development): Spaces, tabs, and line breaks used to separate text or make source easier to read.
- [width attribute](https://www.ask-codey.com/glossary/width-attribute): An attribute that supplies an element's intended width in CSS pixels.

## Apprentice

- [<abbr>](https://www.ask-codey.com/glossary/abbr): The element for an abbreviation or acronym, optionally with its expansion in a title attribute.
- [<address>](https://www.ask-codey.com/glossary/address): The element for contact information associated with an article or the document.
- [<article>](https://www.ask-codey.com/glossary/article): The element for self-contained content that could be reused or distributed independently.
- [<aside>](https://www.ask-codey.com/glossary/aside): The element for content indirectly related to the surrounding content.
- [<blockquote>](https://www.ask-codey.com/glossary/blockquote): The element for a section quoted from another source.
- [<button>](https://www.ask-codey.com/glossary/button): The element for a button that can submit, reset, or perform a scripted action.
- [<caption>](https://www.ask-codey.com/glossary/caption): The element that provides a title or explanation for its table.
- [<cite>](https://www.ask-codey.com/glossary/cite): The element for the title of a creative work.
- [<code>](https://www.ask-codey.com/glossary/code): The element for a fragment of computer code.
- [<col>](https://www.ask-codey.com/glossary/col): The element that represents one or more columns within a colgroup.
- [<colgroup>](https://www.ask-codey.com/glossary/colgroup): The element that represents a group of columns in a table.
- [<fieldset>](https://www.ask-codey.com/glossary/fieldset): The element that groups related form controls and labels.
- [<footer>](https://www.ask-codey.com/glossary/footer): The element for footer information belonging to its nearest section or the page.
- [<header>](https://www.ask-codey.com/glossary/header): The element for introductory or navigational content belonging to a page or section.
- [<input>](https://www.ask-codey.com/glossary/input-html): The element that creates a data-entry control selected by its type attribute.
- [<kbd>](https://www.ask-codey.com/glossary/kbd): The element for user input, commonly keyboard input.
- [<label>](https://www.ask-codey.com/glossary/label): The element that provides a caption for a form control.
- [<legend>](https://www.ask-codey.com/glossary/legend): The element that captions a fieldset.
- [<main>](https://www.ask-codey.com/glossary/main): The element for the document body's dominant, unique content.
- [<mark>](https://www.ask-codey.com/glossary/mark): The element for text highlighted because it is relevant in the current context.
- [<nav>](https://www.ask-codey.com/glossary/nav): The element for a major group of navigation links.
- [<optgroup>](https://www.ask-codey.com/glossary/optgroup): The element that groups related options inside a select control.
- [<option>](https://www.ask-codey.com/glossary/option): The element representing one choice in a select control or datalist.
- [<pre>](https://www.ask-codey.com/glossary/pre): The element for preformatted text whose whitespace is significant.
- [<q>](https://www.ask-codey.com/glossary/q): The element for a short quotation that stays within surrounding text.
- [<s>](https://www.ask-codey.com/glossary/s): The element for content that is no longer accurate or relevant.
- [<samp>](https://www.ask-codey.com/glossary/samp): The element for sample output from a program or computing system.
- [<script>](https://www.ask-codey.com/glossary/script-javascript-2): The element that embeds or references code to be executed in the browser.
- [<search>](https://www.ask-codey.com/glossary/search): The element for controls used to search or filter content.
- [<section>](https://www.ask-codey.com/glossary/section): The element for a standalone thematic section that normally has a heading.
- [<select>](https://www.ask-codey.com/glossary/select-html): The element that lets a user choose from a list of options.
- [<small>](https://www.ask-codey.com/glossary/small): The element for side comments such as copyright text or legal fine print.
- [<sub>](https://www.ask-codey.com/glossary/sub): The element for subscript text required by typographic convention.
- [<sup>](https://www.ask-codey.com/glossary/sup): The element for superscript text required by typographic convention.
- [<tbody>](https://www.ask-codey.com/glossary/tbody): The element that groups a table's main rows.
- [<textarea>](https://www.ask-codey.com/glossary/textarea): The element for editing a multi-line plain-text value.
- [<tfoot>](https://www.ask-codey.com/glossary/tfoot): The element that groups a table's summary or footer rows.
- [<thead>](https://www.ask-codey.com/glossary/thead): The element that groups a table's header rows.
- [<time>](https://www.ask-codey.com/glossary/time): The element for a date, time, duration, or machine-readable date-time value.
- [<u>](https://www.ask-codey.com/glossary/u): The element for text with a non-textual annotation, such as a spelling mark.
- [<var>](https://www.ask-codey.com/glossary/var-html): The element for a variable or placeholder in a mathematical or programming expression.
- [Ancestor](https://www.ask-codey.com/glossary/ancestor): An ancestor is a programming term when dealing with hierarchical documents, such as HTML…
- [autocomplete](https://www.ask-codey.com/glossary/autocomplete): An attribute that provides guidance for automatically filling a form control.
- [autofocus](https://www.ask-codey.com/glossary/autofocus): A Boolean attribute requesting focus for an element when its document or dialog becomes active.
- [Checkbox](https://www.ask-codey.com/glossary/checkbox): An input control representing an independently selected on-or-off choice.
- [checked](https://www.ask-codey.com/glossary/checked): A Boolean attribute that sets the initial selected state of a checkbox or radio button.
- [Color input](https://www.ask-codey.com/glossary/color-input): An input control for choosing a color.
- [colspan](https://www.ask-codey.com/glossary/colspan): The number of columns a table cell spans.
- [Constraint validation](https://www.ask-codey.com/glossary/constraint-validation): The browser process that checks whether supported form controls meet their declared rules.
- [Data table](https://www.ask-codey.com/glossary/data-table): A table that represents relationships between data arranged in rows and columns.
- [Date input](https://www.ask-codey.com/glossary/date-input): An input control for a calendar date without a time zone.
- [disabled](https://www.ask-codey.com/glossary/disabled): A Boolean attribute that makes a control unavailable and normally excludes it from submission.
- [Document outline](https://www.ask-codey.com/glossary/document-outline): The hierarchy of sections and headings that organizes a document's content.
- [Email input](https://www.ask-codey.com/glossary/email-input): An input control that expects one or more email addresses.
- [File input](https://www.ask-codey.com/glossary/file-input): An input control that lets a user choose files for submission.
- [for attribute](https://www.ask-codey.com/glossary/for-attribute): The label attribute whose value matches the id of the control it labels.
- [Form](https://www.ask-codey.com/glossary/form): A section containing controls that collect information for submission.
- [Form action](https://www.ask-codey.com/glossary/form-action): The URL that receives a submitted form's data.
- [Form control name](https://www.ask-codey.com/glossary/form-control-name): The name used as a key for a control's value in submitted form data.
- [Form control value](https://www.ask-codey.com/glossary/form-control-value): The data currently held by a form control.
- [Form encoding type](https://www.ask-codey.com/glossary/form-encoding-type): The format used to encode form data for a POST submission.
- [Form method](https://www.ask-codey.com/glossary/form-method): The HTTP method or dialog behavior used when a form is submitted.
- [GET form](https://www.ask-codey.com/glossary/get-form-submission): A form submission that encodes form data into the URL's query.
- [Heading hierarchy](https://www.ask-codey.com/glossary/heading-hierarchy): The ordered heading levels that communicate how page sections relate.
- [Hidden input](https://www.ask-codey.com/glossary/hidden-input): A non-visible input that contributes a name and value during form submission.
- [Image input](https://www.ask-codey.com/glossary/image-input): A graphical submit button whose value includes the selected image coordinates.
- [Input type](https://www.ask-codey.com/glossary/input-type): The input attribute value that determines the control's data and behavior.
- [Landmark](https://www.ask-codey.com/glossary/landmark): A meaningful page region that helps users and assistive technology navigate the document.
- [Local date and time input](https://www.ask-codey.com/glossary/local-date-and-time-input): An input control for a date and time without a time-zone value.
- [max](https://www.ask-codey.com/glossary/max-html): The highest valid value accepted by a supported form control.
- [maxlength](https://www.ask-codey.com/glossary/maxlength): The maximum number of characters a user can enter into a supported control.
- [min](https://www.ask-codey.com/glossary/min-html): The lowest valid value accepted by a supported form control.
- [minlength](https://www.ask-codey.com/glossary/minlength): The minimum number of characters required for a valid user-entered value.
- [Month input](https://www.ask-codey.com/glossary/month-input): An input control for a year and month.
- [multiple](https://www.ask-codey.com/glossary/multiple): A Boolean attribute that allows more than one value where the control supports it.
- [Number input](https://www.ask-codey.com/glossary/number-input): An input control for a numerical value.
- [Password input](https://www.ask-codey.com/glossary/password-input): A text input that visually obscures its value while it is entered.
- [pattern](https://www.ask-codey.com/glossary/pattern): A regular expression that a supported text control's complete value must match.
- [placeholder](https://www.ask-codey.com/glossary/placeholder): A short hint displayed inside an empty text-like control.
- [POST form submission](https://www.ask-codey.com/glossary/post-form-submission): A form submission that sends form data in the request body.
- [Radio button](https://www.ask-codey.com/glossary/radio-button): An input control representing one choice from a group sharing the same name.
- [Range input](https://www.ask-codey.com/glossary/range-input): An input control for selecting an approximate number within a range.
- [readonly](https://www.ask-codey.com/glossary/readonly-html): A Boolean attribute that prevents editing while keeping the control usable and submittable.
- [Replaced element](https://www.ask-codey.com/glossary/replaced-element): An element like img or video whose content comes from outside CSS.
- [required](https://www.ask-codey.com/glossary/required): A Boolean attribute that requires a control to have a valid value before submission.
- [Reset button](https://www.ask-codey.com/glossary/reset-button): A button that restores form controls to their initial values.
- [rowspan](https://www.ask-codey.com/glossary/rowspan): The number of rows a table cell spans.
- [scope attribute](https://www.ask-codey.com/glossary/scope-attribute): An attribute that states which row, column, or group a header cell applies to.
- [Search input](https://www.ask-codey.com/glossary/search-input): A text input intended for search terms.
- [selected](https://www.ask-codey.com/glossary/selected): A Boolean attribute that sets an option as initially selected.
- [Semantic HTML](https://www.ask-codey.com/glossary/semantic-html): Using HTML elements whose names defined their purpose, rather than generic counterparts.
- [step](https://www.ask-codey.com/glossary/step): The allowed value interval for a supported numeric, date, or time control.
- [Submit button](https://www.ask-codey.com/glossary/submit-button): A button that starts submission of its associated form.
- [Table data cell](https://www.ask-codey.com/glossary/table-data-cell): A cell containing table data.
- [Table header cell](https://www.ask-codey.com/glossary/table-header-cell): A cell that labels a row, column, or group of cells.
- [Table row](https://www.ask-codey.com/glossary/table-row): A horizontal group of header and data cells.
- [Telephone input](https://www.ask-codey.com/glossary/telephone-input): An input control intended for a telephone number.
- [Text input](https://www.ask-codey.com/glossary/text-input): A single-line input control for ordinary text.
- [Time input](https://www.ask-codey.com/glossary/time-input): An input control for a time of day without a time zone.
- [URL input](https://www.ask-codey.com/glossary/url-input): An input control that expects an absolute URL.
- [Validity state](https://www.ask-codey.com/glossary/validity-state): The set of results describing why a form control's value is valid or invalid.
- [Week input](https://www.ask-codey.com/glossary/week-input): An input control for a numbered week of a year.

## Journeyman

- [\_blank target](https://www.ask-codey.com/glossary/blank-target): A target keyword requesting a new top-level browsing context, commonly a new tab.
- [<area>](https://www.ask-codey.com/glossary/area): The element that defines one clickable region and destination in an image map.
- [<audio>](https://www.ask-codey.com/glossary/audio): The element that embeds sound content and can provide browser playback controls.
- [<base>](https://www.ask-codey.com/glossary/base): The element that sets the base URL used to resolve relative URLs in a document.
- [<bdi>](https://www.ask-codey.com/glossary/bdi): The element that isolates text whose direction may differ from its surroundings.
- [<bdo>](https://www.ask-codey.com/glossary/bdo): The element that overrides the normal bidirectional ordering of its text.
- [<canvas>](https://www.ask-codey.com/glossary/canvas): The element that provides a bitmap drawing surface normally controlled through scripting.
- [<details>](https://www.ask-codey.com/glossary/details): The element that contains additional information a user can reveal or hide.
- [<dialog>](https://www.ask-codey.com/glossary/dialog): The element that represents a dialog box or other temporary interactive component.
- [<embed>](https://www.ask-codey.com/glossary/embed): The element that embeds external content handled by the browser or a supported plugin.
- [<iframe>](https://www.ask-codey.com/glossary/iframe): The element that embeds another HTML page as a nested browsing context.
- [<link>](https://www.ask-codey.com/glossary/link): The element that declares a relationship between the document and another resource.
- [<map>](https://www.ask-codey.com/glossary/map-html): The element that defines a collection of interactive areas for an image map.
- [<meta>](https://www.ask-codey.com/glossary/meta): The element for metadata that cannot be expressed by title, base, link, style, or script.
- [<noscript>](https://www.ask-codey.com/glossary/noscript): The element that provides alternate HTML when scripting is disabled or unsupported.
- [<object>](https://www.ask-codey.com/glossary/object-html): The element that embeds an external resource and can contain fallback content.
- [<picture>](https://www.ask-codey.com/glossary/picture): The element that offers image sources for responsive selection before a required img element.
- [<rp>](https://www.ask-codey.com/glossary/rp): The element providing fallback parentheses for browsers that do not render ruby annotations.
- [<rt>](https://www.ask-codey.com/glossary/rt): The element containing ruby pronunciation or annotation text.
- [<ruby>](https://www.ask-codey.com/glossary/ruby): The element that groups base text with its ruby annotations.
- [<source>](https://www.ask-codey.com/glossary/source): The element that supplies an alternative media or image resource for its parent.
- [<summary>](https://www.ask-codey.com/glossary/summary): The element that provides the visible label or summary for its parent details element.
- [<track>](https://www.ask-codey.com/glossary/track): The element that adds timed text data, such as captions, to audio or video.
- [<video>](https://www.ask-codey.com/glossary/video): The element that embeds video content and can provide browser playback controls.
- [<wbr>](https://www.ask-codey.com/glossary/wbr): The element that marks a place where a browser may break a line if needed.
- [Accessible name](https://www.ask-codey.com/glossary/accessible-name): The text assistive technology uses to identify an interface element.
- [accesskey](https://www.ask-codey.com/glossary/accesskey): A global attribute suggesting a keyboard shortcut for activating or focusing an element.
- [ARIA role](https://www.ask-codey.com/glossary/aria-role): A role that communicates an element's purpose to accessibility tools when native semantics are insufficient.
- [aria-describedby](https://www.ask-codey.com/glossary/aria-describedby): An ARIA attribute that identifies elements providing an accessible description.
- [aria-hidden](https://www.ask-codey.com/glossary/aria-hidden): An ARIA attribute that removes an element and its descendants from the accessibility tree when true.
- [aria-label](https://www.ask-codey.com/glossary/aria-label): An ARIA attribute that supplies an accessible name as a text value.
- [aria-labelledby](https://www.ask-codey.com/glossary/aria-labelledby): An ARIA attribute that uses other elements' text to form an accessible name.
- [Art direction](https://www.ask-codey.com/glossary/art-direction): Providing differently composed or cropped images for different presentation conditions.
- [autoplay](https://www.ask-codey.com/glossary/autoplay): A Boolean attribute requesting that media start playing as soon as allowed.
- [Bidirectional isolation](https://www.ask-codey.com/glossary/bidirectional-isolation): Keeping one text segment's direction from unexpectedly affecting surrounding bidirectional text.
- [Canonical link](https://www.ask-codey.com/glossary/canonical-link): A link identifying the preferred URL for content available through multiple URLs.
- [Captions track](https://www.ask-codey.com/glossary/captions-track): A text track containing dialogue and relevant sound information for people who cannot hear the audio.
- [Character encoding declaration](https://www.ask-codey.com/glossary/character-encoding-declaration): Markup near the start of a document that declares its text encoding as UTF-8.
- [contenteditable](https://www.ask-codey.com/glossary/contenteditable): A global attribute indicating whether the user can edit an element's content.
- [Custom data attribute](https://www.ask-codey.com/glossary/custom-data-attribute): An attribute beginning with data- that stores page-specific data on an element.
- [defer](https://www.ask-codey.com/glossary/defer): A Boolean classic-script attribute that delays execution until parsing finishes while preserving document order.
- [dir attribute](https://www.ask-codey.com/glossary/dir-attribute): The attribute that sets left-to-right, right-to-left, or automatically determined text direction.
- [Document language](https://www.ask-codey.com/glossary/document-language): The primary human language of a document or element's text.
- [Document metadata](https://www.ask-codey.com/glossary/document-metadata): Information about a document, such as its title, encoding, language, and related resources.
- [draggable](https://www.ask-codey.com/glossary/draggable): A global attribute indicating whether an element can be dragged through native drag and drop.
- [External script](https://www.ask-codey.com/glossary/external-script): A script loaded from a separate resource through a script element's src attribute.
- [Favicon](https://www.ask-codey.com/glossary/favicon): An icon associated with a website or page for browser tabs, bookmarks, and similar interfaces.
- [hidden](https://www.ask-codey.com/glossary/hidden): A global attribute indicating that an element is not currently relevant and should not be presented.
- [Image candidate](https://www.ask-codey.com/glossary/image-candidate): One image resource the browser may choose from a responsive image source set.
- [Image map](https://www.ask-codey.com/glossary/image-map): An image with defined regions that link to different destinations.
- [Inline script](https://www.ask-codey.com/glossary/inline-script): Script code written directly inside a script element.
- [lang attribute](https://www.ask-codey.com/glossary/lang-attribute): The attribute that declares the human language of an element's content.
- [Lazy loading](https://www.ask-codey.com/glossary/lazy-loading): Delaying an off-screen resource until it is likely to be needed.
- [Left-to-right text](https://www.ask-codey.com/glossary/left-to-right-text): Text whose main reading direction proceeds from left to right.
- [Link relationship](https://www.ask-codey.com/glossary/link-relationship): A keyword describing how the current document and a linked resource are related.
- [loading attribute](https://www.ask-codey.com/glossary/loading-attribute): An attribute that hints whether an image or iframe should load immediately or lazily.
- [loop](https://www.ask-codey.com/glossary/loop): A Boolean attribute that makes media begin again after it finishes.
- [Media controls](https://www.ask-codey.com/glossary/media-controls): Browser-provided controls for playing, pausing, seeking, and adjusting media.
- [Meta content](https://www.ask-codey.com/glossary/meta-content): The value supplied for a named piece of metadata.
- [Meta description](https://www.ask-codey.com/glossary/meta-description): A short document summary supplied as metadata, often used by search and sharing tools.
- [Meta name](https://www.ask-codey.com/glossary/meta-name): The name identifying which document-level metadata a meta element supplies.
- [Module script](https://www.ask-codey.com/glossary/module-script): A script processed as a JavaScript module with imports, strict mode, and module scoping.
- [muted](https://www.ask-codey.com/glossary/muted): A Boolean attribute that initially silences an audio or video element.
- [noopener](https://www.ask-codey.com/glossary/noopener): A link relationship that prevents a newly opened page from receiving an opener reference.
- [noreferrer](https://www.ask-codey.com/glossary/noreferrer): A link relationship that omits referrer information and also prevents an opener relationship.
- [open attribute](https://www.ask-codey.com/glossary/open-attribute): A Boolean attribute that makes a details element expanded or a dialog displayed.
- [Pixel density descriptor](https://www.ask-codey.com/glossary/pixel-density-descriptor): A srcset descriptor stating an image resource's intended pixel-density scale.
- [preload](https://www.ask-codey.com/glossary/preload): A media attribute that hints how much content the browser should load before playback.
- [rel attribute](https://www.ask-codey.com/glossary/rel-attribute): The attribute containing one or more link relationship keywords.
- [Responsive image](https://www.ask-codey.com/glossary/responsive-image): An image setup that lets the browser select a suitable resource for the display and layout.
- [Right-to-left text](https://www.ask-codey.com/glossary/right-to-left-text): Text whose main reading direction proceeds from right to left.
- [Ruby annotation](https://www.ask-codey.com/glossary/ruby-annotation): Small pronunciation or explanatory text shown with East Asian base text.
- [sizes](https://www.ask-codey.com/glossary/sizes): An attribute describing an image's expected rendered width under different conditions.
- [spellcheck](https://www.ask-codey.com/glossary/spellcheck): A global attribute that hints whether editable text should receive spelling and grammar checking.
- [srcset](https://www.ask-codey.com/glossary/srcset): An attribute listing image candidates with width or pixel-density descriptors.
- [style attribute](https://www.ask-codey.com/glossary/style-attribute): A global attribute containing CSS declarations applied directly to one element.
- [Stylesheet link](https://www.ask-codey.com/glossary/stylesheet-link): A link element that loads an external CSS stylesheet.
- [Subtitles track](https://www.ask-codey.com/glossary/subtitles-track): A text track translating or transcribing dialogue for viewers who can hear but may not understand it.
- [tabindex](https://www.ask-codey.com/glossary/tabindex): A global attribute that controls whether and where an element participates in sequential focus navigation.
- [target attribute](https://www.ask-codey.com/glossary/target-attribute): An attribute that names where a linked or submitted document should open.
- [Text direction](https://www.ask-codey.com/glossary/text-direction): The direction in which text and inline content progress.
- [Text track](https://www.ask-codey.com/glossary/text-track): Time-based text or metadata associated with audio or video.
- [translate](https://www.ask-codey.com/glossary/translate): A global attribute indicating whether an element's text and translatable attribute values should be translated.
- [usemap](https://www.ask-codey.com/glossary/usemap): The attribute that connects an image to a map element by fragment identifier.
- [Video poster](https://www.ask-codey.com/glossary/video-poster): An image displayed in a video element before video frames are available.
- [Viewport metadata](https://www.ask-codey.com/glossary/viewport-metadata): Metadata that guides how a page's viewport is sized and scaled on mobile devices.
- [Width descriptor](https://www.ask-codey.com/glossary/width-descriptor): A srcset descriptor stating an image resource's intrinsic width in pixels.

## Freelancer

- [<datalist>](https://www.ask-codey.com/glossary/datalist): The element that supplies suggested options to an associated input without limiting entry to those options.
- [<meter>](https://www.ask-codey.com/glossary/meter): The element that displays a measured value within a known range.
- [<output>](https://www.ask-codey.com/glossary/output): The element that represents the result of a calculation or user action.
- [<progress>](https://www.ask-codey.com/glossary/progress): The element that displays completion progress for a task.
- [<slot>](https://www.ask-codey.com/glossary/slot): The element that marks where assigned light-DOM content appears inside a shadow tree.
- [<template>](https://www.ask-codey.com/glossary/template): The element that stores inert HTML fragments for later use.
- [accept attribute](https://www.ask-codey.com/glossary/accept-attribute): A file-input attribute that hints which file types the user should select.
- [allow attribute](https://www.ask-codey.com/glossary/allow-attribute): An iframe attribute that controls which Permissions Policy features its content may use.
- [Auto popover](https://www.ask-codey.com/glossary/auto-popover): A popover mode with light dismissal that normally closes other auto popovers.
- [Autonomous custom element](https://www.ask-codey.com/glossary/autonomous-custom-element): A custom element with its own hyphenated tag name.
- [capture attribute](https://www.ask-codey.com/glossary/capture-attribute): A file-input attribute that hints a preferred camera or microphone source for new media.
- [crossorigin](https://www.ask-codey.com/glossary/crossorigin): An attribute that configures a cross-origin request and whether credentials are included.
- [Custom element](https://www.ask-codey.com/glossary/custom-element): An author-defined HTML element whose behavior is registered through the Custom Elements API.
- [Customized built-in element](https://www.ask-codey.com/glossary/customized-built-in-element): A custom element that extends a built-in HTML element and uses the is attribute.
- [Declarative shadow DOM](https://www.ask-codey.com/glossary/declarative-shadow-dom): HTML syntax that creates a shadow root from a template element during parsing.
- [download attribute](https://www.ask-codey.com/glossary/download-attribute): An anchor or area attribute that requests a download and can suggest a filename.
- [Download link](https://www.ask-codey.com/glossary/download-link): A hyperlink that suggests downloading its destination instead of navigating to it.
- [enterkeyhint](https://www.ask-codey.com/glossary/enterkeyhint): A global attribute that hints which action label or icon to show on a virtual enter key.
- [exportparts](https://www.ask-codey.com/glossary/exportparts): An attribute that exposes selected part names from a nested shadow tree through its host.
- [Focusable area](https://www.ask-codey.com/glossary/focusable-area): A page region or control that can become the target of keyboard focus.
- [form attribute](https://www.ask-codey.com/glossary/form-attribute): An attribute that associates a form control with a form by id, even when it is outside that form.
- [Form data set](https://www.ask-codey.com/glossary/form-data-set): The ordered name-and-value entries constructed from a form for submission.
- [Form owner](https://www.ask-codey.com/glossary/form-owner): The form element associated with a form control or other form-associated element.
- [Form submission](https://www.ask-codey.com/glossary/form-submission): The process of constructing form data and sending or navigating it to the form's destination.
- [Form-associated element](https://www.ask-codey.com/glossary/form-associated-element): An element with form-related behavior that can be connected to a form owner.
- [Hint popover](https://www.ask-codey.com/glossary/hint-popover): A popover mode for transient hints that can coexist with an auto popover.
- [Iframe sandbox](https://www.ask-codey.com/glossary/iframe-sandbox): Restrictions applied to content in an iframe through its sandbox attribute.
- [Implicit submission](https://www.ask-codey.com/glossary/implicit-submission): Form submission triggered by an action such as pressing Enter in a text control.
- [inert](https://www.ask-codey.com/glossary/inert): A global attribute that prevents an element and its descendants from receiving focus or user interaction.
- [inputmode](https://www.ask-codey.com/glossary/inputmode): A global attribute that hints which input interface, such as a numeric keyboard, would be useful.
- [integrity attribute](https://www.ask-codey.com/glossary/integrity-attribute): An attribute containing hashes used to verify a fetched script or stylesheet.
- [itemid](https://www.ask-codey.com/glossary/itemid): An attribute giving a typed microdata item a global identifier.
- [itemprop](https://www.ask-codey.com/glossary/itemprop): An attribute that assigns one or more property names to data in an element.
- [itemref](https://www.ask-codey.com/glossary/itemref): An attribute that adds properties from elements outside a microdata item's descendants.
- [itemscope](https://www.ask-codey.com/glossary/itemscope): A Boolean attribute that creates a new microdata item.
- [itemtype](https://www.ask-codey.com/glossary/itemtype): An attribute containing vocabulary URLs that define a microdata item's type.
- [Light dismiss](https://www.ask-codey.com/glossary/light-dismiss): Closing a temporary interface by interacting outside it or making a platform close request.
- [list attribute](https://www.ask-codey.com/glossary/list-attribute): The input attribute whose value identifies a datalist containing suggestions.
- [Manual popover](https://www.ask-codey.com/glossary/manual-popover): A popover mode that remains open until explicitly hidden.
- [Microdata](https://www.ask-codey.com/glossary/microdata): HTML attributes that add machine-readable items and name-value properties to document content.
- [Microdata item](https://www.ask-codey.com/glossary/microdata-item): A group of microdata properties describing one thing.
- [Modal dialog](https://www.ask-codey.com/glossary/modal-dialog): A dialog that makes the rest of its document inert until the dialog closes.
- [Multipart form data](https://www.ask-codey.com/glossary/multipart-form-data): A form encoding that separates entries into parts and supports file uploads.
- [Named slot](https://www.ask-codey.com/glossary/named-slot): A slot identified by name so matching host children can be assigned to it.
- [nonce attribute](https://www.ask-codey.com/glossary/nonce-attribute): A one-use token that a Content Security Policy can require on allowed inline script or style elements.
- [Non-modal dialog](https://www.ask-codey.com/glossary/non-modal-dialog): A displayed dialog that allows interaction with the rest of the document.
- [part attribute](https://www.ask-codey.com/glossary/part-attribute): An attribute naming parts inside a shadow tree so external CSS can select them.
- [ping attribute](https://www.ask-codey.com/glossary/ping-attribute): An anchor or area attribute listing URLs to notify when the hyperlink is followed.
- [Ping URL](https://www.ask-codey.com/glossary/ping-url): A URL notified when a user follows a hyperlink, when hyperlink auditing is enabled.
- [Popover](https://www.ask-codey.com/glossary/popover): An element displayed in the top layer using built-in showing, hiding, and dismissal behavior.
- [popover attribute](https://www.ask-codey.com/glossary/popover-attribute): A global attribute that turns an element into a popover.
- [Popover target](https://www.ask-codey.com/glossary/popover-target): A popover element connected to a button or input that can show or hide it.
- [referrerpolicy](https://www.ask-codey.com/glossary/referrerpolicy): An attribute that controls which referrer information is sent when fetching or navigating.
- [Sequential focus navigation](https://www.ask-codey.com/glossary/sequential-focus-navigation): Moving focus through eligible page controls in an ordered sequence, commonly with the Tab key.
- [Shadow host](https://www.ask-codey.com/glossary/shadow-host): An element to which a shadow root is attached.
- [Shadow root](https://www.ask-codey.com/glossary/shadow-root): A document fragment that forms the root of a component's encapsulated shadow tree.
- [shadowrootmode](https://www.ask-codey.com/glossary/shadowrootmode): A template attribute that requests an open or closed declarative shadow root.
- [Slot assignment](https://www.ask-codey.com/glossary/slot-assignment): The process that matches a shadow host's children with slots in its shadow tree.
- [srcdoc](https://www.ask-codey.com/glossary/srcdoc): An iframe attribute containing the HTML document that should be embedded directly.
- [Subresource integrity](https://www.ask-codey.com/glossary/subresource-integrity): A security feature that checks a fetched resource against an expected cryptographic hash.
- [Successful control](https://www.ask-codey.com/glossary/successful-control): A form control that contributes its name and value to submitted form data.
- [Template contents](https://www.ask-codey.com/glossary/template-contents): The separate document fragment containing the child markup of a template element.
- [URL-encoded form data](https://www.ask-codey.com/glossary/url-encoded-form-data): A form encoding that represents name-and-value pairs using URL-style escaping.

## Master

- [Adoption agency algorithm](https://www.ask-codey.com/glossary/adoption-agency-algorithm): The tree-construction procedure that repairs certain misnested formatting elements.
- [Character token](https://www.ask-codey.com/glossary/character-token): A parser token representing one or more characters of document text.
- [Comment node](https://www.ask-codey.com/glossary/comment-node): A DOM node containing the text of an HTML comment.
- [Comment token](https://www.ask-codey.com/glossary/comment-token): A parser token representing an HTML comment.
- [Content category](https://www.ask-codey.com/glossary/content-category): A named group of HTML elements that share roles used by content-model rules.
- [Content model](https://www.ask-codey.com/glossary/content-model): The rule describing which kinds of child content an HTML element may contain.
- [Context element](https://www.ask-codey.com/glossary/context-element): The element whose type and state guide how an HTML fragment is parsed.
- [Custom element content model](https://www.ask-codey.com/glossary/custom-element-content-model): The rules governing which children are valid in an author-defined custom element.
- [Data state](https://www.ask-codey.com/glossary/data-state): The tokenizer's normal state for reading document text and recognizing markup.
- [Document node](https://www.ask-codey.com/glossary/document-node): The DOM node representing the whole document and serving as the tree's root.
- [DOM tree](https://www.ask-codey.com/glossary/dom-tree): The in-memory tree of document, element, text, comment, and other nodes produced from HTML.
- [Element node](https://www.ask-codey.com/glossary/element-node): A DOM node representing an element and its attributes.
- [Embedded content](https://www.ask-codey.com/glossary/embedded-content): Content that imports or draws another resource, such as an image, video, iframe, or canvas.
- [End-of-file token](https://www.ask-codey.com/glossary/end-of-file-token): The token indicating that no more input remains for the parser.
- [Flow content](https://www.ask-codey.com/glossary/flow-content): The broad category containing most elements allowed in a document body.
- [Foreign content](https://www.ask-codey.com/glossary/foreign-content): SVG or MathML content parsed within an HTML document under its own namespace rules.
- [Foster parenting](https://www.ask-codey.com/glossary/foster-parenting): Parser behavior that relocates certain misplaced table content outside the table structure.
- [Heading content](https://www.ask-codey.com/glossary/heading-content): The h1 through h6 and hgroup elements used to identify section headings.
- [HTML conformance checker](https://www.ask-codey.com/glossary/html-conformance-checker): A tool that reports whether markup follows the requirements placed on HTML authors.
- [HTML fragment parsing](https://www.ask-codey.com/glossary/html-fragment-parsing): Parsing an HTML string as a fragment using a supplied element as its context.
- [HTML namespace](https://www.ask-codey.com/glossary/html-namespace): The namespace URI that identifies ordinary HTML elements in the DOM.
- [HTML parser](https://www.ask-codey.com/glossary/html-parser): The browser component that turns HTML source into a document tree.
- [HTML serialization](https://www.ask-codey.com/glossary/html-serialization): Converting a document or node tree back into HTML text.
- [HTML tokenization](https://www.ask-codey.com/glossary/html-tokenization): The parsing stage that converts input characters into tags, text, comments, and end-of-file tokens.
- [Implied end tag](https://www.ask-codey.com/glossary/implied-end-tag): An end tag the parser acts as though it encountered when certain later markup makes it unnecessary.
- [Insertion mode](https://www.ask-codey.com/glossary/insertion-mode): The parser state that selects tree-construction rules based on the current document context.
- [Integration point](https://www.ask-codey.com/glossary/integration-point): A location in SVG or MathML where the parser can switch between foreign-content and HTML parsing rules.
- [Interactive content](https://www.ask-codey.com/glossary/interactive-content): Elements specifically intended for user interaction, such as links and form controls.
- [List of active formatting elements](https://www.ask-codey.com/glossary/list-of-active-formatting-elements): Parser state used to reconstruct and repair formatting elements across misnested markup.
- [MathML namespace](https://www.ask-codey.com/glossary/mathml-namespace): The namespace URI that identifies inline MathML elements in a document tree.
- [Metadata content](https://www.ask-codey.com/glossary/metadata-content): Elements that set presentation, behavior, relationships, or other information about a document.
- [Node document order](https://www.ask-codey.com/glossary/node-document-order): The order nodes appear when a document tree is traversed from beginning to end.
- [Obsolete feature](https://www.ask-codey.com/glossary/obsolete-feature): An old HTML feature that current documents should not use.
- [Optional tag](https://www.ask-codey.com/glossary/optional-tag): A start or end tag that HTML syntax permits an author to omit under specific conditions.
- [Palpable content](https://www.ask-codey.com/glossary/palpable-content): Content expected to contribute something users can perceive rather than existing only as structure.
- [Parse error](https://www.ask-codey.com/glossary/parse-error): HTML input that violates a parsing rule but is still handled through defined recovery behavior.
- [Parser error recovery](https://www.ask-codey.com/glossary/parser-error-recovery): The standardized rules browsers follow to build a predictable document tree from malformed HTML.
- [Parser-blocking script](https://www.ask-codey.com/glossary/parser-blocking-script): A script whose fetching or execution pauses further HTML parsing.
- [Parser-inserted script](https://www.ask-codey.com/glossary/parser-inserted-script): A script element created by the HTML parser rather than by a DOM operation.
- [Phrasing content](https://www.ask-codey.com/glossary/phrasing-content): Elements and text used within paragraphs and other runs of text.
- [RAWTEXT state](https://www.ask-codey.com/glossary/rawtext-state): A tokenizer state that treats content as text until the matching end tag, while recognizing no character references.
- [RCDATA state](https://www.ask-codey.com/glossary/rcdata-state): A tokenizer state that treats content as text but still recognizes character references and the matching end tag.
- [Script preparation](https://www.ask-codey.com/glossary/script-preparation): The HTML processing steps that determine a script's type, source, readiness, and execution behavior.
- [Script-supporting element](https://www.ask-codey.com/glossary/script-supporting-element): An element used to support scripts without directly representing page content, such as script or template.
- [Sectioning content](https://www.ask-codey.com/glossary/sectioning-content): Elements that create major thematic sections, including article, aside, nav, and section.
- [Stack of open elements](https://www.ask-codey.com/glossary/stack-of-open-elements): The parser's ordered list of elements that have started but have not yet been fully closed.
- [SVG namespace](https://www.ask-codey.com/glossary/svg-namespace): The namespace URI that identifies inline SVG elements in a document tree.
- [Tag token](https://www.ask-codey.com/glossary/tag-token): A parser token representing a start tag or end tag and its parsed attributes.
- [text/html MIME type](https://www.ask-codey.com/glossary/text-html-mime-type): The media type that identifies a resource as an HTML document parsed with HTML syntax.
- [Tokenizer state](https://www.ask-codey.com/glossary/tokenizer-state): The current rule set the HTML tokenizer uses to interpret the next input characters.
- [Transparent content model](https://www.ask-codey.com/glossary/transparent-content-model): A content model that largely adopts the content rules of the element's surrounding context.
- [Tree construction](https://www.ask-codey.com/glossary/tree-construction): The parsing stage that uses tokens to create and arrange nodes in the document tree.
- [XHTML syntax](https://www.ask-codey.com/glossary/xhtml-syntax): XML syntax used to represent HTML elements under XML parsing rules.

[More subjects in Web Basics](https://www.ask-codey.com/glossary/groups/web-basics)

Source: https://www.ask-codey.com/glossary/subjects/html