3D-CAD-Prouses the Qt framework to draw and manage its interface. This framework is used in a wide range of applications, so the 3D-CAD-Prointerface is very classical and presents no particular difficulty to understand. Most buttons are standard and will be found where you expect them File → Open, Edit → Paste, etc. Here is the look of 3D-CAD-Prowhen you open it for the first time, just after installing, showing you the start center:
 

The main Interface

See a full explanation in Interface.

1. The main view area, which can contain different tabbed windows, principally the 3D view.

2. The 3D view, showing the geometrical objects in the document.

3. The tree view (part of the combo view), showing the hierarchy and construction history of objects in the document; it can also display the task panel for active commands.

4. The property editor (part of the combo view), which allows viewing and modifying properties of the selected objects.

5. The selection view, which indicates the objects or sub-elements of objects (vertices, edges, faces) that are selected.

6. The report view (or output window), where messages, warnings and errors are shown.

7. The Python console, where all the commands executed are printed, and where you can enter Python code.

8. The status bar, where some messages and tooltips appear.

9. The toolbar area, where the toolbars are docked.

10. The workbench selector, where you select the active workbench.

11. The standard menu, which holds basic operations of the program.

The main concept behind the 3D-CAD-Prointerface is that it is separated into workbenches. A workbench is a collection of tools suited for a specific task, such as working with meshes, or drawing 2D objects, or constrained sketches. You can switch the current workbench with the workbench selector. You can customize the tools included in each workbench, add tools from other workbenches or even self-created tools, that we call macros. Widely used starting points are the PartDesign Workbench and Part Workbench.