American writers Jack London (1876-1916) and Jack Kerouac (1922-1969) were two famous bearers of this name. It is also borne by the actor Jack Nicholson (1937-) and the golfer Jack Nicklaus (1940-). Apart from Nicklaus, none of these famous bearers were given the name Jack at birth.
In the United Kingdom this form has been bestowed more frequently than John since the 1990s, being the most popular name for boys from 1996 to 2008.
A notable bearer is content creator Patrick "Patch" Lacey, better known as TierZoo.