The .stp file extension, also known as STEP (Standard for the Exchange of Product Data), represents a 3D graphic file format used for storing 3D models and assemblies. It is a widely used international standard (ISO 10303) for exchanging data between different CAD (Computer-Aided Design) systems. STEP files are designed to be platform-independent and application-independent, meaning they can be opened and viewed on various CAD software regardless of the original software used to create them. This interoperability makes STEP files ideal for sharing 3D models with collaborators who may be using different CAD programs. STEP files store geometric and topological information about the 3D model, including surfaces, curves, and solids. They can also contain metadata such as material properties, manufacturing information, and assembly structure. The format supports both solid and surface models and is capable of representing complex geometries accurately. STEP files are often used in manufacturing, engineering, and product design workflows to ensure seamless data exchange and collaboration.