SketchUp - 3D for Everyone
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
MicroStation - 3D CAD modelling software for architecture and engineering.
FreeCAD - An open-source parametric 3D modeler
TurboCAD - TurboCAD is a CAD software suite, with several different feature levels.
Autodesk AutoCAD - Autodesk AutoCAD is a commercial computer-aided design (CAD) and drafting software application.