Reverses an action that is in the undo list. You can view the undo list and undo more than one action by clicking the arrow next to the Undo button on the Quick Access toolbar.
Note:
Certain operations clear the undo list. For example, when you save a file or transition from one environment to another, the undo list is cleared. When the undo list is cleared, the Undo command is not available until more actions are added to the list.
You can change the number of actions that can be undone using the Options command.
View manipulations are not included in the undo list.
When working with an assembly, operations that modify multiple documents or solve the assembly are placed in the undo list. For example, you can move faces in multiple parts or use in-place activation to modify a part and these operations are placed in the undo list.