It's good easy to learn to use for MEP Drawings Brics CAD can use Cad & BIM extension file DWG # Philemon _Dubai
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
SketchUp - 3D for Everyone
ArchiCAD - ArchiCAD 16 enables BIM modeling with a new green approach to planning. Create anything you need with ArchiCAD's flexible new features for design.
FreeCAD - An open-source parametric 3D modeler
Revit - Use Revit® BIM (Building Information Modeling) software to drive efficiency and accuracy across the project lifecycle, from conceptual design, visualization, and analysis to fabrication and construction.
DraftSight - Discover Dassault Systèmes®' DRAFTSIGHT™ Professional CAD software that lets you create, edit, view and markup any kind of 2D drawing. Learn more here.