The history of the Black Armband goes back a long time but it can be most recently seen in a game of cricket, where Michael Clarke (former captain of the Australian cricket team) wore a black armband to honour the late Australian cricketer Phillip Hughes (RIP).
It is seen as a symbol of mourning for the deceased. This is represented by wearing a black armband above the elbow. It is a sign of respect and that those who have passed have not been forgotten.
It is particularly seen at the first event, meeting, gathering or function after the individual have passed