Looking for information on 3D file formats

I'm looking for some good resources to help me understand the different file formats used in 3D modeling software (.stl, .dcm, .wrl).  Ideally I would like to familiarize myself with the what the file structure is, how it differs from parametric files (like .sldpt), and how I can best tailor a solidworks file when exporting to these different formats.  Appreciate any pointers in the right directon, thanks!