What is a SKP File Type?
The main file type used by SketchUp is the SKP file, which allows you to create, view, and share concepts quickly and easily. When you create a new document and save it to SketchUp, the SKP file is created to store the document and its contents. You can also use SKP files to store SketchUp components, which are objects, such as a door or window, that you can reuse to save time. They can be manufactured by you or another user and can be imported into an SKP document for insertion into your model.
SketchUp also saves your document for archiving purposes. If you want to save your SKP document you can save it as a .SKB backup file.
SketchUp was originally developed by @ Last Software, but was purchased by Google in 2006. "SketchUp 5" is the latest release by @ Last. It was developed by Google, but now it belongs to Trimble. SketchUp templates created with SketchUp can be shared with Google Earth using the 3D Warehouse function.