Royal dukedoms in the United Kingdom
In the British peerage, a royal duke is a member of the British royal family, entitled to the titular dignity of prince and the style of "His Royal Highness" who holds a dukedom. Dukedoms are the highest titles in the British roll of peerage and the holders of these particular dukedoms are Princes of the Blood Royal. The holders of the dukedoms are royal not the titles themselves. They are titles created and bestowed on legitimate sons and male-line grandsons of the British monarch, usually upon reaching their majority or marriage. The titles can be inherited but cease to be called "royal" once they pass beyond the grandsons of a monarch. As with any peerage, once the title becomes extinct, it may subsequently be recreated by the reigning monarch at any time.
Knight Bachelor
The dignity of Knight Bachelor is the basic and lowest rank of a man who has been knighted by the monarch but not as a member of one of the organised orders of chivalry; it is a part of the British honours system. Knights Bachelor are the most ancient sort of British knight (the rank existed during the 13th century reign of King Henry III), but Knights Bachelor rank below knights of chivalric orders.