Likewise, it is not necessary to model an entire floor plan in 3D - such as doors, windows, furniture, and all other essential elements - when it is possible to simply produce a top-view layout that employs symbols to indicate locations and dimensions of the floor plan. For example, if you are CNC milling a flat object such as a business sign, you only need to create the object from one view point. There are several practical applications for limiting your design to two dimensions. This contrasts with 3D CAD, where the projected views are generated using a 3D model of the object on three planes (x, y, and z-axes).