The Motion Picture Association of America uses the following ratings:
General audiences (G): All ages admitted.
Parental guidance suggested (PG): Some material may not be suitable for
children.
Parents strongly cautioned (PG-13): Some material may be inappropriate for
children under 13.
Restricted (R): Under 17 requires accompanying parent or adult guardian.
NC-17: No one 17 and under admitted.
Although they are not required to, most film producers and distributors
submit their films to be rated by the MPAA. After MPAA board members view
the film, they don't evaluate the film's quality or lack thereof, but they
consider criteria such as theme, violence, language, nudity, sensuality and
drug abuse. The board's decision on the rating of a film is decided by
majority vote.
Click here for more detailed information on the MPAA's ratings process. For a look at how film ratings have change over the years, search for "film ratings" here.