Research into age certificates and the BBFC - Miss Georgiou

The British Board of Film Classification (BBFC),is a non-governmental organisation, funded by the film industry and responsible for the national classification and censorship of films within the United Kingdom. The BBFC currently issues the following certificates:
U: Universal - All ages admitted, there is nothing unsuitable for children.

PG: Parental Guidance - Suitable for general viewing, but some scenes may be unsuitable for younger children. May contain mild language and sex/drugs references. May contain moderate violence if jusified by context (e.g. fantasy)

12 Home media only since 2002. Nobody younger than 12 can rent or buy a 12-rated VHS, DVD, Blu-ray Disc, UMD or game. The content guidelines are identical to those used for the 12A certificate.

12A:

Cinema only. Children younger than 12 may see the film if they are accompanied by an adult, however it is generally not recommended that children under 12 years should watch the film. Films under this category can contain mature themes, discrimination, soft drugs, infrequent strong language and moderate violence, sex references and nudity. Sexual activity may be briefly and discreetly portrayed. Sexual violence may be implied or briefly indicated.

15: Only those 15 years are admitted. Nobody younger than 15 can rent or buy a 15-rated VHS, DVD, Blur-ray Disc, UMD or game, or watch a film in the cinema with this rating. Films under this category can contain adult themes, hard drugs, frequent strong language and limited use of very strong language, strong violence and strong sex references, and nudity without graphic detail. Sexual activity may be potrayed but without any strong detail. Sexual violence may be shown if discreet and justified by context.

18: Only adults are admitted. Nobody younger than 18 can rent or buy an 18-rated VHS, DVD Blu-ray Disc, UMD or game, or watch a film in the cinema with this rating. Films under this category do not have limitation on the bad language that is used. Hard drugs are generally allowed, and explicit sex references along with detailed sexual activity are also allowed. Scenes of strong real sex may be permitted if justified by the context. Very strong, gory and/or sadistic violence is usually permitted. Strong sexual violence is permitted unless it is eroticised or excessively graphic.

R18: Can only be shown at licensed adult cinemas or sold at licensed sex shops, and only to adults, those aged 18 or over. Films under this category always contain hardcore pornography, defined as material intended for sexual stimulation and containing clear images of sexual activity.