on the toolbar or
choose Undo from the Edit menu. The menu always shows the type of
action that will be undone. Undo and redo operations.
Undo.
When creating and editing objects, mistakes are inevitable. So, you may need to cancel a sequence of recent actions and return the document to its previous correct state. The Undo command can be used for this purpose.
To reverse the last action, click the Undo button on the toolbar or
choose Undo from the Edit menu. The menu always shows the type of
action that will be undone.
 |
 |
| Ctrl+Z | Cmd+Z |
| Alt+BkSp |
The number of consecutive actions that can be undone is limited. The default value is 30. You may specify your value under the Settings tab in the Document Properties dialog (File/Document Properties). The higher the number, the more memory the program requires to store the actions.
Redo
Redo operation is inverse to Undo. Use it to reverse the
latest Undo operation. Click the Redo button 
on the toolbar, or
select Redo under the Edit menu.
| |
|
| Ctrl+Y | Cmd+Y |