For those of you who visit London as tourists, you may not know that those guardsmen you see are not all dressed the same.
There are five Regiments of Foot Guards and the way to tell them apart is by the spacing of their tunic buttons, their collar badges and their bearskin plumes:
The Grenadier Guards have evenly spaced buttons, grenade collar badges and a white plume worn on left side; The Coldstream Guards have buttons in pairs, garter star badge and red plume worn on right; The Scots Guards have buttons arranged in threes, thistle badge and no plume; The Irish Guards have buttons in fours, shamrock badge and a blue plume on the right, then finally The Welsh Guards have buttons in fives, a leek badge and a white-green-white plume on the left.
Coldstream Guards
An officer of The Grenadier Guards; his bearskin is taller and of finer manufacture. Also he has gold tunic facings.