Why does internet explorer often tend to misplace material on a page compared to Firefox and Netscape who display similar? Are there certain codes to avoid using because explorer doesn't play fair?

depends on what codes you are talking about.

some are proprietary (only work in certain browsers).

ie also has a different "box model" for spacing.

netscape and ff are cousins, so they will be similar.
ie is a totally different company made product, thus different ideals on outcomes.

Great explanation....I will just try and work around it.

Thanks a bunch!!

Also, if you're using CSS which isn't proprietary - such as padding, margins, borders, et al. in the box model - and it's just a case of IE not wanting to play because Microsoft tends to like to do things their own way, issues can often be resolved by forcing IE out of its quirks mode into a more standards-compliant mode using an document type definition like XHTML 1.0 Strict. This solves problems like IE's CSS box model (http://www.w3.org/TR/2005/WD-CSS21-20050613/box.html) variances cited by pb&j, among others.

Thanks J for the explanation. Once you think you have learned one small lesson, you view your work in IE and realize you that you really didn't learn anything. Back to the drawing board. Thanks again.