MathML (Mathematical Markup Language) is an industry standard adopted by the World Wide Web Consortium (W3C). MathML is the approved way to express Math Equations on the Web. MathML is written in XML syntax and describes structure and content. MathML provides the highest level of accessibility to math within digital documents. MathML is a universal format that will convert into audible, visible, tactile and machine readable formats.
The best way to create digital accessible math is by using webpages W3C Math.
Math Support Finder - online tool that helps identify the right combination of tools to read math accessibly
MathML Cloud - open source tool to create math content accessible to all readers
MathType is an add-in that can inserted into: Word 2010, Excel, PowerPoint, Google Docs, and Mac Office.
MathJax - A Javascript display engine that works in all browsers
Firefox and Safari have MathML support built-in.