AutoCAD - User Coordinate System (UCS and UCCS)
About the video course "2D Design, 3D Modeling, and Visualization in AutoCAD 2020, 3ds Max 2020, and V-Ray Next": http://autocad-profi.ru/sait_2d_3d_au...
Working with the UCS is important not only in 3D space but also in regular drawing. It's also important to understand how the coordinate system works. A dynamic coordinate system allows you to quickly build 3D models of any complexity.