The Last Post is one of a number of bugle calls in military tradition that mark the phases of the day.

In military tradition, the Last Post is the bugle call that signifies the end of the day's activities. It is also sounded at military funerals to indicate that the soldier has gone to his final rest, and at commemorative services such as Anzac Day and Remembrance Day

During the evening, a duty officer moved around a unit’s position, checking that sentry posts were manned and sending off-duty soldiers to their beds. 

The ‘first post’ was sounded when the duty officer started rounds, and a final bugle call indicated the completion of these rounds when the last sentry post was reached.