HTML
The coding language to create
hypertext documents on the
World Wide Web . HTML is a way to format text by placing marks ("tags") around the text (like old-fashioned typesetting code).
An acronym for a
Hyper
Text
Markup
Language
DTD .  HTML is the language used to tag various parts of a Web document so browsing software will know how to display that document's links, text, graphics and attached media. Your are viewing an HTML document at this moment. The popular HTML and the emerging HTML are subsets of the GML text scripting conceived in1969 IBM researchers depicting
Generalized
Markup
Languages (and not-so-coincidentally the lead researchers were named
Goldfarb,
Mosher, and
Lorie).   Between 1978 and 1987, Dr. Charles F. Goldfarb led the team that developed the SGML Standard GML that is became International Standard ISO 8879.  In 1990, Tim Berners-Lee led a team of particle physicists that invented the World Wide Web using a very small part of SGML that became the widely known and used scripting language known as Hypertext Markup Language (HTML).  SGML is tremendously powerful but inefficient and complex. 
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(HyperText Markup Language) -- The coding language used to create Hypertext documents for use on the World Wide Web. HTML looks a lot like old-fashioned typesetting code, where you surround a block of text with codes that indicate how it should appear, additionally, in HTML you can specify that a block of text, or a word, is linked to another file on the Internet. HTML files are meant to be viewed using a World Wide Web Client Program, such as Netscape or Mosaic.
The coding applied to text files that allows them to appear as formatted hypermedia documents on the World Wide Web.
Hypertext Markup Language - a language (or format) used for creating hypertext documents on the World Wide Web. This is the format used to create Web pages.
(Hyper Text Markup Language). A system of marking up, or tagging, a document so it can be published on the World Wide Web. An author incorporates HTML markup in his or her document to define the function (as distinct from the appearance) of different text elements. The appearance of these text elements is not defined at the authoring stage; instead, formatting is applied when a browser decides how it is going to display the text elements.