In the Royal Navy this is the name given to the flag raising ceremony that happens every day when a ship is in harbour - "Colours! Face aft and salute". At the end of the ceremony the order "Carry on " is given.
Colours represent the pride of a regimental unit, whether in the army, air force or navy. The concept of colours originated from the Middle Ages, when lord and barons would lead their men to battle. Given the scale of battle, there was a need to establish a rallying point, so they used coloured flags to denote rallying points, hence the term "Colours". The colours were carried by the bravest subaltern (the subaltern tradition still continues today) and since the falling of the colours represented defeat of the forces, troops would often attack them. Hence, there was a need for escorts, who were pikemen back then. In modern days, although colours no longer exist on the battlefield, they are still respected and many of the traditions that were started during the Middle Ages still exist today.
For American spelling of colour see color.
