HTML (HyperText Markup Language) is the most basic building block of the Web. It describes and defines the content of a webpage. Other technologies besides HTML are generally used to describe a webpage's appearance/presentation (CSS) or functionality (JavaScript).

"HyperText" refers to links that connect webpages to one another, either within a single website or between websites. Links are a fundamental aspect of the Web. By uploading content to the Internet and linking it to pages created by other people, you become an active participant in the World Wide Web.

HTML uses "markup" to annotate text, images, and other content for display in a Web browser. HTML markup includes special "elements" such as <head>, <title>, <body>, <header>, <article>, <section>, <p>, <div>, <span>, <img>, and many others.

The articles below will help you learn more about HTML.

  • HTML Reference

    In our extensive HTML reference section, you'll find the details about every element and attribute in HTML.

  • HTML Tutorials

    For articles about how to use HTML, as well as tutorials and complete examples, check out our HTML Learning Area.

  • HTML Introduction

    If you're new to Web development, be sure to read our HTML Basics article to learn what HTML is and how to use it.


HTML element reference
Browse a list of all HTML elements.
HTML reference
HTML consists of elements, each of which may be modified by some number of attributes. HTML documents are connected to each other with links.
Inline elements
HTML elements are usually "inline" elements or "block-level" elements. An inline element occupies only the space bounded by the tags that define it.
Block-level elements
HTML elements are usually "block-level" elements or "inline" elements. A block-level element occupies the entire space of its parent element (container), thereby creating a "block."
CORS enabled image
The crossorigin attribute, in combination with an appropriate CORS header, allows images defined by the <img> element to be loaded from foreign origins and used in a <canvas> element as if they were being loaded from the current origin.
CORS settings attributes
Some HTML elements that provide support for CORS, such as <img> or <video>, have a crossorigin attribute (crossOrigin property), which lets you configure the CORS requests for the element's fetched data.
Focus management in HTML
The activeElement DOM attribute and the hasFocus() DOM method help you track and control a user's interactions with elements on a webpage.
Global attributes
Global attributes may be specified on all HTML elements, even those not specified in the standard. This means that any non-standard elements must still permit these attributes, even though those elements make the document HTML5-noncompliant.
HTML attribute reference
Elements in HTML have attributes. These are additional values that configure the elements or adjust their behavior in various ways.
Link types
In HTML, various link types can be used to establish and define the relationship between two documents. Link types include <a>, <area>, and <link>.
Media formats supported by the HTML audio and video elements
The <audio> and <video> elements allow you to play audio and video media. These elements provide a browser-native alternative to similar capabilities found in Adobe Flash and other plug-ins.
Using the application cache
Application caching lets web-based applications run offline. You can use the Application Cache (AppCache) interface to specify resources that the browser should cache and make available to offline users. Applications that are cached load and work correctly even if users click the refresh button when they are offline.

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Our HTML Learning Area features multiple modules that teach HTML from the ground up — no previous knowledge required.

Introduction to HTML
This module sets the stage, getting you used to important concepts and syntax such as looking at applying HTML to text, how to create hyperlinks, and how to use HTML to structure a webpage.
Multimedia and embedding
This module explores how to use HTML to include multimedia in your web pages, including the different ways that images can be included, and how to embed video, audio, and even entire other webpages.
HTML forms
Forms are a very important part of the Web — these provide much of the functionality you need for interacting with web sites, e.g. registering and logging in, sending feedback, buying products, and more. This module gets you started with creating the client-side parts of forms.
Use HTML to solve common problems
Provides links to sections of content explaining how to use HTML to solve very common problems when creating a webpage: dealing with titles, adding images or videos, emphasizing content, creating a basic form, etc.

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