STL, an abbreviation for stereolithography, is an interchangeable file format that represents 3-dimensional surface geometry. The file format finds its usage in several fields such as rapid prototyping, 3D printing, and computer-aided manufacturing. It represents a surface as a series of small triangles, known as facets, where each facet is described by a perpendicular direction and three points representing the vertices of the triangle.
Files with .POTX extension represent Microsoft PowerPoint template presentations that are created with Microsoft PowerPoint 2007 and above. This format was created to replace the POT file format that is based on the binary file format and is supported with PowerPoint 97-2003. The files generated can be used to create presentations that have same layout and other settings required to be applied to new files. These settings can include styles, backgrounds, colour palette, fonts and defaults. Such files are generated in order to create ready-to-use template files for official use.
You can also convert STL into many other file formats. Please see the complete list below.