The Most Honourable Order of the Bath (formerly the Most Honourable Military Order of the Bath) is a British order of chivalry founded by George I on 18 May 1725. The name derives from the elaborate medieval ceremony for appointing a knight, which involved bathing (as a symbol of purification) as one of its elements. The knights so created were known as "Knights of the Bath". George I "erected the Knights of the Bath into a regular Military Order". He did not (as is commonly believed) revive the Order of the Bath, since it had never previously existed as an Order, in the sense of a body of knights who were governed by a set of statutes and whose numbers were replenished when vacancies occurred.

The Order consists of the Sovereign (currently Queen Elizabeth II), the Great Master (currently The Prince of Wales), and three Classes of members:

Knight Grand Cross (GCB) or Dame Grand Cross (GCB)

Knight Commander (KCB) or Dame Commander (DCB)

Companion (CB)

More Info: en.wikipedia.org