The BBFC ratings system in the UK has evolved over time, starting with only two ratings in 1912 - Universal for all ages and Adult restricted to adults. Additional ratings were introduced, including an 'X' rating in 1951 to restrict access to some films. Further changes included an 'H' rating for horror films in 1932 and an 'AA' rating in 1970 to restrict access to those under 14. The 12A rating introduced in more recent years allows those 12 and over to see a film alone but with a parent if not deemed suitable. Ratings are determined through public consultation and research to provide guidelines on content around issues like language, violence, sex and drugs.