AutoCAD is a computer-aided design (CAD) software architects, engineers, and designers use to create precise 2D and 3D designs. AutoCAD 2D is used to create two-dimensional drawings, while AutoCAD 3D is used to create three-dimensional models. The software allows for precise measurements, detailed annotations, and easy modification of designs. AutoCAD can be used in various fields, including architecture, engineering, product design, and manufacturing.