British humour is a somewhat general term applied to certain comedic motifs that are often prevalent in comedic acts originating in Great Britain and its current or former colonies. Comedy acts and television programs typical of British humour include Monty Python, Benny Hill, and Keeping Up Appearances to name a few that have become quite popular outside of the British Isles. At times, however, such humour can seem puzzling to non-British speakers of English (references to English slang terms or people, who are unknown internationally for example) while certain Commonwealth nations (such as Australia, Canada and South Africa) tend to find it more familiar. Many UK comedy TV shows typical of British humour have been internationally popular, and have been a strong avenue for the export and representation of British culture to an international audience.
This is how Wikipedia defined British Humour, focusing more on the culture, theories and technicalities. On a lighter note, the following signs divulge us how hilarious they really are.