Question about .stp vs .stl files

[jimjimajimjima]

If I simply wanted to get a prototype 3d printed would I need an .stp file, an .stl file or both.

Also, what is the difference between the two? Thanks.

[awerby]

You don't need a STP file; that's a format that only a few systems (like Catia) use. It's useful for storing parametric model data, but that's not necessary for 3D printing. You want a STL file, which is a simple collection of triangles called out by their vertices. If you've got a choice, go for binary STL rather than ASCII.

Andrew Werby