U3D (Universal 3D)

The U3D file is a 3D file format (Universal 3D) developed by a consortium of well-known companies in 2005 with the idea of creating a standardized file format for storing 3D data, including mesh vertices, textures, bones, and effects.

U3D files are binary in nature, containing a block-based structure that, following later revisions, could be extended with custom blocks.