As is not uncommon in the web development world, I was so mad at IE I was ready to delete my bootcamp partition off my Mac and microwave my windows 7 disc.  I was working on a website and it would render fine in any browser but IE.  As it turns out, IE thought it should be in compatibility mode.  Here’s the fix – a meta declaration:

<meta http-equiv="X-UA-Compatible" content="IE=8" />

You tell IE to render in its version 8 rendering engine.  For those daring enough, you can replace 8 with edge.  However, you can never tell what bugs will be in future versions of IE.

A List Apart has a good and thorough article on doctypes and rendering in IE 8.

–Ben

Sources:  A List Apart