In the early 1990's, The World Wide Web Consortium's Html became the standard markup language for publishing on the World Wide Web. It has since evolved and has become an extensible and very powerful means of representing interactive Internet documents. In terms of representing mathematics however, Html has little support.
In the first versions of Html , no support for mathematics was included. It was not until 1993 that the first intent of embedding mathematics within Internet documents was attempted in the Html+ draft [5] presented by the World Wide Web Consortium. Equations were represented directly as Html+ using an SGML [8] based notation, inspired by LATEX 's approach.
In 1994, the World Wide Web Consortium went further in mathematics Internet publishing by presenting the Html 3.0 draft [6] (which later was officially published as the Html 3.2 [7] specification with a few modifications) which offered a more comprehensive support. They claimed ``Html math is powerful enough to describe the range of math expressions you can create in common word processing packages, as well as being suitable for rendering to speech.''
Nonetheless, both drafts failed because of lack of interest from popular browser vendors. But even though the mathematical ideas in the Html 3.2 specification were never fully deployed, people started thinking more carefully about mathematics, and how they could be represented on the WWW.
In the meantime, while the World Wide Web Consortium and other societies continued working on developing mathematical support for Internet documents, other solutions to transmitting mathematics on the web arose. The lack of a standard approach to uniformly represent mathematics on the Internet pushed mathematicians and scientists to use a variety of different techniques to achieve this purpose. Let us give a brief overview of the main ones.