3D file formats can be grouped in 3 categories

Binary files (stl, 3ds)

Ascii files (fbx, ply, obj)

xml files (dae, x3d)

However some of the file formats my have more than one implementations as stl, that can be binary or ascii)

Xml files are rather big but have the advantage to follow a strict syntax and be able to parse and use by a external program as a python script. Additionally x3d is the ISO/IEC 19775 standard and some html5 web browsers can show it. x3d is a successor of vrml ISO/IEC 14772.