DraftSight 2D CAD software, which lets users create, view, and edit DWG and DXF files, is free -- and it comes with its own online social-networking communities.

What is CAD? you might be wondering if you're considering a career in architecture, engineering or product design. Jobs in ...

6] QCAD. QCAD is another open-source CAD software like LibreCAD, except that its scope is limited to 2-Dimensional drawings. However, this is one of the best software products for 2D drawings.

LibreCAD is a free and open-source 2D CAD application that lets you edit DWG files. Using it, you can edit DWG as well as DXF files in it. You can even design a new drawing from scratch using it.