SketchUp - 3D for Everyone
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
AutoCAD Arch - Design and document more efficiently with the AutoCAD Architecture toolset, created specifically for architects.
DraftSight - Discover Dassault Systèmes®' DRAFTSIGHT™ Professional CAD software that lets you create, edit, view and markup any kind of 2D drawing. Learn more here.
MicroStation - 3D CAD modelling software for architecture and engineering.
nanoCAD - nanoCAD is a pro-grade 2D CAD system with native DWG support and full customizability.