HTML (HyperText Markup Language) is the most basic building block of the Web. It defines the meaning and structure of web content. Other technologies besides HTML are generally used to describe a web page's appearance/presentation (CSS) or functionality/behavior (JavaScript).
"Hypertext" refers to links that connect web pages 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 , , , , , , , , , , , , , , , , , , , , , , , , and many others.
An HTML element is set off from other text in a document by "tags", which consist of the element name surrounded by " < " and " >". The name of an element inside a tag is case-insensitive. That is, it can be written in uppercase, lowercase, or a mixture. For example, the tag can be written as , , or in any other way. However, the convention and recommended practice is to write tags in lowercase.
The articles below can help you learn more about HTML.
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.
For articles about how to use HTML, as well as tutorials and complete examples, check out our HTML Learning Area.
In our extensive HTML reference section, you'll find the details about every element and attribute in HTML.
Our HTML Learning Area features multiple modules that teach HTML from the ground up — no previous knowledge required.
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 web page.
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.
Representing tabular data on a webpage in an understandable, accessible way can be a challenge. This module covers basic table markup, along with more complex features such as implementing captions and summaries.
Forms are a very important part of the Web — these provide much of the functionality you need for interacting with websites, e.g. registering and logging in, sending feedback, buying products, and more. This module gets you started with creating the client-side/front-end parts of forms.
Provides links to sections of content explaining how to use HTML to solve very common problems when creating a web page: dealing with titles, adding images or videos, emphasizing content, creating a basic form, etc.
HTML consists of elements, each of which may be modified by some number of attributes. HTML documents are connected to each other with links.
Browse a list of all HTML elements.
Elements in HTML have attributes. These are additional values that configure the elements or adjust their behavior in various ways.
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 elements are usually "inline-level" or "block-level" elements. An inline-level element occupies only the space bounded by the tags that define it. A block-level element occupies the entire space of its parent element (container), thereby creating a "block box".
HTML comments are used to add explanatory notes to the markup or to prevent the browser from interpreting specific parts of the document.
HTML is comprised of several kinds of content, each of which is allowed to be used in certain contexts and is disallowed in others. Similarly, each context has a set of other content categories it can contain and elements that can or can't be used in them. This is a guide to these categories.
Historical information on quirks mode and standards mode.
This article covers most of the ways you use CSS to add color to HTML content, listing what parts of HTML documents can be colored and what CSS properties to use when doing so.