The .SKP file extension refers to SketchUp document created with the SketchUp software. This file is a very popular format for 3D modelling.

The sketchup utility software is used for quick and easy to use 3D model designs that can be generated without consuming much time. The file format offers real-like 3D feel with the ability to create, view, modify and share the 3D models in real time. As the program is developed by google, the sketch up files can be used in some of the google services like Google Earth.It is becoming a very popular online format nowadays for 3D models of geographical objects.