Convert x3db to stl

What is the difference between .x3db and .stl?

Description: X3DB is a 3D graphics file format used to represent 3D models and scenes using the X3D standard. It is a binary format, providing higher compression and faster loading times than the equivalent X3D XML format. X3DB files can be used to represent characters, environments, and objects, and can be opened and edited using a variety of 3D graphics software.; Stl is the standard 3D data transmission file format mainly used for 3D printing. STL contains surface geometry descriptions of 3D objects and it uses a series of triangles to describe the surface geometry of a 3D model.