STEP

STEP (ISO 10303) is an international standard for CAD data exchange, preserving precise geometry with NURBS surfaces and solid modeling. Widely used in mechanical design, engineering, and manufacturing, it retains parametric features and assembly structures for lossless transfer between mainstream CAD software, unlike mesh formats like STL/OBJ.

STEP is oriented toward engineering precision rather than real-time rendering; browsers and game engines typically require conversion to mesh formats. A suitable workflow: complete design in CAD, export STEP for archiving or collaboration, then convert to STL/GLB for previewing, printing, or Web display. The extensions .stp and .step are identical.