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 Object window.
If the Auto Apply button is on, you can preview the cross-section in the Object window
To get a new object from Clipping, click Ok.