Using this menu you can create cross-section views (clipping planes) of your mesh.
To start, click on the New button.
Now you can define the parameters of your cross-section: Orientation (X-Y, X-Z or Y-Z); Distance between the opposite extremities of the object, if it is set to 0.5 the object is split in two halves; and Rotation (in angle degrees) around X (Y to Z) and around Y (X to Z). If the Show preview button is on, you can see the clipping plane in the 3D Viewer.
The plane and the cut object
If the Auto Apply button is on, you can preview the cross-section in the 3D Viewer.
The cross-section
To get a new object from Clipping, click Apply.