<canvas> is a new HTML element which can be used to draw graphics using scripting (usually JavaScript). It can for instance be used to draw graphs, make photo compositions or do simple (and not so simple) animations.

<canvas> was first introduced by Apple for the Mac OS X Dashboard and later implemented in Safari. Gecko-based applications support this new element starting with Gecko 1.8 (i.e. Firefox 1.5 and later). Opera 9 supports as well.

The <canvas> element is part of the WhatWG Web applications 1.0 specification also known as HTML 5.

a demo here: http://www.tapper-ware.net/canvas3d/ (use arrows / space bar to navigate)

about the canvas tag: http://developer.mozilla.org/en/docs/Canvas_tutorial