So that the user knows that there is an accelerator associated with a component, the accelerator needs to be displayed. If a button with an accelerator is within a primary or secondary window, or within a Pulldown Menu system from its MenuBar, it is activatable whenever the input focus is in the window or the MenuBar system. An accelerator must be activatable from the window or component associated with the accelerator. If your application uses mnemonics, the Label for the component with the mnemonic contains the character that is its mnemonic. A mnemonic is a single character that can be associated with any component that contains a text Label.
Mnemonics provide a fast way of selecting a component from the keyboard.
So that the user knows that there is a mnemonic associated with a selection, the mnemonic is underlined in the Label of the selection by the toolkit. In order for a mnemonic to be underlined, the Label for a selection needs to contain the mnemonic character. Putting the mnemonic in parentheses following the Label provides visual consistency. The user must be able to activate a mnemonic by pressing either the lowercase or the uppercase variant of the mnemonic key. When the location cursor is within a Menu or MenuBar, pressing the mnemonic key of a component within that Menu or MenuBar moves the location cursor to the component and activates it.