User-Defined Tools
Placing the cursor over the User-defined Tools command rolls out a sub-menu containing custom-made commands that use external applications. You can create these commands in the Tools tab of the Customize dialog. Clicking one of these custom commands executes the action associated with this command.
The User-Defined Tools | Customize command opens the Tools tab of the Customize dialog (in which you can create the custom commands that appear in the menu of the User-Defined Tools command.)