The system checks all incoming keyboard messages to see whether they match any existing accelerator-table entries (in either the system message queue or the application message queue). The system first checks the accelerator table associated with the active frame window; if it does not find a match, the system uses the accelerator table associated with the message queues. If the keyboard input event corresponds to an accelerator-table entry, the system changes the WM_CHAR message to a WM_COMMAND, WM_SYSCOMMAND, or WM_HELP message, depending on the attributes of the accelerator table. If the keyboard input event does not correspond to an accelerator-table entry, the system passes the WM_CHAR message to the keyboard-focus window.

Applications should use accelerator tables to implement keyboard shortcuts rather than translate command keystrokes. For example, if an application uses the F2 key to save a document, the application should create a keyboard accelerator entry for the F2 virtual key so that, when pressed, the F2 key generates a WM_COMMAND message rather than a WM_CHAR message.