Upper class titles and meaning

[stoogmeister]

What are the meanings of the different upper class titles e.g duke, earl, marquess, etc...?

[Artemis]

They are just ranks similar to military rankings.

[IndieSinger]

Duke - In Great Britain and some other countries: A hereditary title of nobility, ranking next below that of prince.

Marquess - A British or Irish hereditary nobleman of the second rank of the peerage, below a duke and above an earl; (also) the eldest son of a British or Irish duke who is also a marquess, who takes his father's second title as a courtesy.

Earl - In England, Scotland, and Ireland, the title of a specific order of rank, corresponding to Count in the nobility of other European nations; in the modern peerage an earl ranks next below a marquis, and next above a viscount.

Any more?