The term "free" in the context of professional CAD software usually refers to specific licensing categories or trial periods: AutoCAD 2013 System Requirements | Article - cadpilot
: Design components are managed as Building Information Modeling (BIM) objects, allowing for dynamic updates across the entire project when changes are made. System Requirements for 64-bit Installation civilcad para autocad 2013 64 bits free
: A minimum of 4 GB is required, though 8 GB is highly recommended for complex 3D modeling. The term "free" in the context of professional
: Windows 7 (Professional, Ultimate, or Enterprise) or Windows 8 with AutoCAD 2013 Service Pack 2 . : Approximately 6 GB for the base AutoCAD
: Approximately 6 GB for the base AutoCAD installation plus additional space for the CivilCAD plugin and project files. Display : 1,280 x 1,024 resolution with True Color. Accessing the "Free" Version
: Create and manage surfaces from surveyed points or digital models to represent project topographies.