HTML5 test document

Having fun with Web standards

This is an HTML5 page for me to have fun with. It is intended to be syntactically valid both as HTML (i.e., `text/html`) and as XHTML (i.e., `application/xhtml+xml`): see the recommendation on polyglot markup for details (although this is not exactly polyglot markup because of the way the inline stylesheet is escaped).

Some demos

Math in MathML

Everyone should know that $2+2=4$ and that ${\int }_{-\infty }^{+\infty }{e}^{-{x}^{2}}dx=\sqrt{\pi }$.

Editable content

This paragraph is editable. By clicking on it (or otherwise selecting it) you should be able to modify it through your web browser.