MathML is an application of XML for describing mathematical notations, and capturing both their structure and content. It aims at integrating mathematical notation into World Wide Web documents so they can be accessible to the visually impaired. As LaTeX, XML is a markup language for representing structured documents. However, in contrast to LaTeX, XML is NOT page layout language. Also, XML is an interchange and manipulation interface designed for machine, and not to be edited by humans.
Firefox (at least 2.0 and up) and Opera (at least 9.52 and up) browsers properly render MathML content on all three platforms (Linux/Mac/Windows). For best rendering installation of additional fonts is suggested.
For proper rendering of MathML, Internet Explorer (version 5.5 and up) browser requires additional plugin from Design Science website.
As far as know, Safari browser does not properly render MathML.
For details of adjusting/testing your Firefox, Opera, or Internet Explorer browsers
for MathML content, read section 7 of my tutorial:
viewing accessible documents with math content.
Installation of Fire Vox (screen and math reader) for Firefox browser described in section 7.2 is optional.