OpenSCAD is used to create solid 3D CAD models. It focuses primarily on object design instead of artistic expression.
It is not an interactive modeler. Instead it is something like a 3D-compiler that reads in a script file that describes the object and renders the 3D model from this script file. OpenSCAD provides two main modeling techniques: first, there is constructive solid geometry (aka CSG); and second there is extrusion of 2D outlines. As data exchange format format for this 2D outlines Autocad DXF files are used. In addition to 2D paths for extrusion it is also possible to read design parameters from DXF files. Besides DXF files OpenSCAD can read and create 3D models in the STL and OFF file formats.