|Type:||3D Animating, Modelling, Programming|
and Rendering Software
|Platform:||OSX, Linux and Windows|
|License:||free (open source)|
|Input Formats:||.stl / .fbx / .x3d / .obj / etc.|
|Output Formats:||.stl / .fbx / .x3d / .obj / .exe / etc.|
Blender is a free open source software for 3D modelling, animating, programming and rendering, and can also be used for 3D printing (Blender can actually be used for a huge scope of applications, but is not optimized for all of them - for example, Blender hasn't got a very powerful game engine, but a good rendering system).
Applications include 3D rendering, photo editing or 3D printable modeling.
There are a lot of ways to learn Blender. The easiest are tutorials from YouTube, or Communities like Stack Overflow.