You can reverse the effect of the last change you made in your design. For example, you might want to experiment with some changes and then reverse those changes.

alt To undo the last changes:
  1. Click Edit | Undo as many times as desired.

You can undo an undo. For example, you might make a change, undo the change and then on second thought decide that you want the change after all.

alt To redo the last undone action:
  1. Click Edit | Redo.

You can undo or redo several actions simultaneously and you can review a list of actions done. For example you might want to undo the last 10 things you changed or examine the history of those changes.

alt To undo or redo several actions at once or view the change history:
  1. Click the down arrow next to the Undo or Redo button.
  2. In the drop-down list select the commands to undo or redo or simply view the history.