LeoCAD is a free and open source CAD software for Linux, Windows and MacOS. Using this LeoCAD CAD software you can create virtual LEGO models. It is released under open source GNU Public License. It completely supports and compatible with the LDraw Standard and related tools. It also supports reads and write of LDR and MPD files. It allows you to share and download models from the Internet. The current LDraw parts library in LeoCAD comes with more than 10,000 different parts.