In many countries, feature films must undergo a vigorous film classification process before they can be released. In the United States, the Motion Picture Association of America (MPAA) is responsible for rating films, however in the UK, the British Board of Film Classification does the job. Throughout the years since the BBFC's inception, there have been many different rating classifications, and the current selection follow a number of strict guidelines.
U (Universal)
It is impossible to predict what might upset any particular child. But a ‘U’ film should be suitable for audiences aged four years and over. ‘U’ films should be set within a positive moral framework and should offer reassuring counterbalances to any violence, threat or horror.
Examples include "Shrek", "Star Wars: Episodes I, IV-VI" and "The Muppets".