Why do div tags render differently in IE8 and Firefox?
Is there a way to have them rendered the same?
This is a very general question, the reason I ask is I am fighting both browsers when using div tags, some elements are not rendering the same.
You may benefit from starting off with a reset.css. This generally fixes any differences between multiple browsers. I suggest Meyer's (online at http://meyerweb.com/eric/tools/css/reset/).
Simply download that .css file, and reference it first before any other css rules/files. This assumes that your problem is with the actual browsers, and not with your markup.