What's the difference between a baron, a duke, and an earl?

Baron, Duke and Earl are titles given to respected men of nobility in most European Countries. Their differences are stated below in terms of definition:
- A Baron is a nobleman of the "lowest rank". In Britain, barons use the title 'Lord'; in other countries they use the title 'Baron'.
- A Duke is a nobleman of the "highest rank". He can also be referred to as a male ruler of a small independent state.
- An Earl is an nobleman of "high rank".
Considering the definitions given, the hierarchy of nobility is in the order: Baron - Earl - Duke (Can be best remembered as BED).

The mnemonic "Do Men Ever Visit Boston" helps in remembering in descending order of Duke, Marquess, Earl, Viscount, Baron.

These are the 5 ranks of peer in the U.K.

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