This document outlines the different rating categories used by the BBFC to classify films for viewing audiences in the UK. It explains the criteria for ratings of U, PG, 12A, 12, 15 and 18. The U rating is generally for all ages, PG suggests parental guidance for young children, 12A and 12 mean no one under 12 should watch without guidance, 15 and 18 mean no one under the age threshold should view. An R18 category covers explicit adult content.