The computerized descendant of typesetting

IDEA N^o 7

MARKUP LANGUAGE

HTML is to the Web what moveable type is to the printing press. As moveable type allows printers to typeset their publications, HTML allows web developers to design a web page. Without it, there would be no Web.

When type was set by hand, a small number of ‘galley proofs’ would be printed for markup by the editor and/or the author. On receipt of the edits, the printer would adjust the type, and print final copies.

The first computer mark-up language, RUNOFF, was created in 1964 by Jerome Saltzer for MIT’s time-sharing system. Inspired by RUNOFF, William Tunnicliffe created a version that worked across different operating systems. Originally called GenCode, it evolved into Standard Generalized Markup Language (SGML).

With the rise of WYSIWYG (what you see is what you get) software at the end of the 80s, it looked like the end of markup language. Nothing could be further from the truth. In 1991, Tim Berners-Lee created the first webpage using a derivative of SGML. He called it Hypertext Markup Language (HTML).

One of the core technologies of the Web, HTML consists of ‘tags’ within a web page that format text, indicate links and embed objects. Tags usually have an opening <BOLD> and closing tag </BOLD>. A web browser reads these tags and composes the webpage according to their instructions. Based on only 18 basic instructions, the simplicity of HTML was a major factor in the proliferation of the Web.

During the browser wars of the mid-90s, different versions of HTML emerged, causing inconsistencies in the way webpages were displayed. To address this, in 1996 Berners-Lee created the World Wide Web Consortium (W3C), which has maintained HTML specifications ever since.

Another markup language widely used on the Web is XML (eXtensible Markup Language). Also developed and maintained by W3C, its purpose is to introduce flexibility, allowing developers to create any tags they need. The main difference between HTML and XML is that HTML is designed to be read by a browser whereas XML is designed to be read by an application of the developer’s choice.

The fifth version of HTML – HTML5 – has been under development since 2007. It adds in-built support for many of the multimedia features required by today’s web users, including audio, video and scaleable vector graphics, avoiding the need for proprietary plug-ins such as Flash. A stable version of HTML5 is due for release by the end of 2014.■

‘Markup language evolved from the marking up of paper manuscripts by editors.’