To Combine Shapes with Union
Use Union to combine two or more shapes into a single shape object. Select the shapes to be combined and choose Graphic > Combine > Union from the main menu. Note that the new shape will adopt the style of the top object in the selection.
To Intersect Two Shapes
Intersecting two shapes results in a new shape that is based on the overlapping area between them. Select two shapes to be intersected and choose Graphic > Combine > Intersect from the main menu. Note that the new shape will adopt the style of the (lower) object being intersected.
HINT: Images can be masked and cropped using non-destructive editing with the Intersect tool. See "Working with Images" for more information.
To Subtract Shapes With Difference
Use Difference when the portion of one shape (the top shape) is to be subtracted from another (bottom) shape. Select the two overlapping shapes to be subtracted from each other and choose Graphic > Combine > Difference from the main menu. Note that the remaining shape maintains its original style.
To Append Shapes Together
Combining like objects into single shapes can make your drawing more efficient. The Append command combines multiple shapes into a single shape object, with overlapping areas excluded from the new shape. Objects do not need to overlap to be appended together. Append is also appropriate for open paths, whereas the others work only with closed paths. Using Union, Intersection or Difference with an open path produces undefined results (though Undo works to correct any unexpected outcomes).
Select two or more shapes to be appended, and choose Graphic > Combine > Append from the main menu. Note that the new shape will adopt the style of the top object in the selection.
To Break Shapes Apart
Objects that have been appended together can be broken apart into their separate components. Choose Graphic > Combine > Break Apart from the main menu.