.ply
PLY modelPolygon File Format
The Polygon File Format, also called the Stanford Triangle Format, devised at Stanford in the 1990s. It stores vertices and faces with extra properties such as per-vertex colour.
3D scans, point clouds and research data.
Opens in MeshLab, CloudCompare, Blender
About PLY files.stl
STL modelStereolithography
A mesh format created by 3D Systems in 1987 for stereolithography printers. It describes a surface only as triangles, with no colour, units or materials, in text or binary form.
Sending models to 3D printers and slicers.
Opens in Cura, PrusaSlicer, Bambu Studio, Blender, Quick Look on Mac
About STL files