canvas - an element to give you a drawing space in JavaScript on your Web pages. It can let you add images or graphs to tool tips or just create dyanmic graphs on your Web pages, built on the fly.
video - add video to your Web pages with this simple tag.
audio - add sound to your Web pages with this simple tag.
HTML 5 Removes Some Elements
There are also some elements in HTML 4 that will no longer be supported by HTML 5. Most are already deprecated, and so shouldn't be surprising, but a few might be difficult:
