HTML (hypertext markup language) originator Tim Berners-Lee developed further upon SGML, making electronic document input language easier to learn and more developer friendly. HTML uses tags to provide formatting that web browsers or web client software understands. The first standards for HTML were established in 1991 and today we are in the middle of the emerging HTML 5 version.
HTML developers write tags like <h1>header size</h1> to identify certain aspects of the document layout. These tags create a layout for the content of the document, including images, tables, paragraphs, backgrounds and much more. There are also tags called meta tags which help search engines identify the content on a particular page. HTML developers create and edit layouts and upload the files to a server which gives access to the document to the clients which it serves including the Internet.