html - vs. . Which to use?

When looking at most sites (including SO), most of them use:

instead of:

• What are the main differences between the two, if any?


• Are there valid reasons to use one instead of the other?


• Are there valid reasons to use combine them?


• Does using

Answer

• Here's a page describing the differences (basically you can put html into a )


• And another page describing why people avoid (Hint: IE6)

Another IE problem when using