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.
Life peer
In the United Kingdom, life peers are appointed members of the peerage whose titles cannot be inherited, in contrast to hereditary peers. In modern times, life peerages, always created at the rank of baron, are created under the Life Peerages Act 1958 and entitle the holders to seats in the House of Lords, presuming they meet qualifications such as age and citizenship. The legitimate children of a life peer are entitled to style themselves with the prefix "The Honourable", although they cannot inherit the peerage itself.