These formatting commands were derived from the commands used by typesetters to manually format documents. Many of the text elements are mentioned in the 1988 ISO technical report TR 9537 Techniques for using SGML, which describes the features of early text formatting languages such as that used by the RUNOFF command developed in the early 1960s for the CTSS (Compatible Time-Sharing System) operating system. Default characteristics for every item of HTML markup are defined in the browser, and these characteristics can be altered or enhanced by the web page designer's additional use of CSS. HTML is a markup language that web browsers use to interpret and compose text, images, and other material into visible or audible web pages. Eleven of these elements still exist in HTML 4. Except for the hyperlink tag, these were strongly influenced by SGMLguid, an in-house Standard Generalized Markup Language (SGML)-based documentation format at CERN. It describes 18 elements comprising the initial, relatively simple design of HTML. The first publicly available description of HTML was a document called 'HTML Tags', first mentioned on the Internet by Tim Berners-Lee in late 1991. In his personal notes of 1990, Berners-Lee listed 'some of the many areas in which hypertext is used' an encyclopedia is the first entry. That year, Berners-Lee and CERN data systems engineer Robert Cailliau collaborated on a joint request for funding, but the project was not formally adopted by CERN. Berners-Lee specified HTML and wrote the browser and server software in late 1990. In 1989, Berners-Lee wrote a memo proposing an Internet-based hypertext system. In 1980, physicist Tim Berners-Lee, a contractor at CERN, proposed and prototyped ENQUIRE, a system for CERN researchers to use and share documents. History Development Tim Berners-Lee in April 2009 A form of HTML, known as HTML5, is used to display video and audio, primarily using the element, together with JavaScript. The World Wide Web Consortium (W3C), former maintainer of the HTML and current maintainer of the CSS standards, has encouraged the use of CSS over explicit presentational HTML since 1997.

The inclusion of CSS defines the look and layout of content. HTML can embed programs written in a scripting language such as JavaScript, which affects the behavior and content of web pages. Browsers do not display the HTML tags but use them to interpret the content of the page. Other tags such as and surround and provide information about document text and may include sub-element tags. Tags such as and directly introduce content into the page.

HTML elements are delineated by tags, written using angle brackets. HTML provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes, and other items.

With HTML constructs, images and other objects such as interactive forms may be embedded into the rendered page. HTML elements are the building blocks of HTML pages. HTML describes the structure of a web page semantically and originally included cues for its appearance. Web browsers receive HTML documents from a web server or from local storage and render the documents into multimedia web pages. It is often assisted by technologies such as Cascading Style Sheets (CSS) and scripting languages such as JavaScript. It defines the meaning and structure of web content. The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser.

Graphical web browser definition