The most popular and common format for 3D modelling is the STL file format. This has also proven to be the most effective format for 3D printing as well, but competing formats are emerging.
STL (short for STereoLithography or Standard Tessellation Language) is a format which was originally developed for the stereolithography CAD software created by 3D Systems.
Today, the file format is supported by most CAD software packages. It is used for 3D printing rapid prototyping and CAM (computer-aided manufacturing). Almost all 3D printable objects available on the popular Thingiverse platform are stored in STL file format (the SKP file you see in the screenshot is a SketchUp file that users can open and modify in the SketchUp software).
A STL file describes the surface geometry of a three-dimensional object without any representation of colour, texture, or other common CAD model attributes.
Rivals to STL File Format
Of course, this isn’t to say that the STL file format is the *only* format for 3D printing. There are various others as well, such as the OBJ file format, which is generally considered to be a universal file format. Another popular format is PLY (Polygon file format), which was originally used for storing 3D scanned objects.
More recently, there have been efforts to launch a new file format, driven by a consortium of major players lead by Microsoft. It’s called The 3MF Consortium, and is proposing a new 3D printing file format, .3MF, claiming that it will streamline and improve the 3D printing process. To implement the format, Microsoft has partnered up other companies like Autodesk, HP, and Shapeways to make their vision a reality.
More details on the 3MF Consortium can be read about on their website, together with preliminary documentation about the .3MF file format on their GitHub page. It’s too early to say whether this will become widely adopted, however, so we’d recommend sticking with the STL file format for the foreseeable future.
Image source: Thingiverse
License: The text of "STL File Format: For Now, the Standard in 3D Printing" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.