What are rated R Movies?

In the United States, movies are rated by the Motion Picture Association of America. To obtain a rating, producers must submit their filmed to be categorized by the MPAA. Issues that the MPAA takes into consideration when rating content include language, nudity, sex, violence, drug use, and adult topics. According to the MPAA, an R-rated film "contains some adult material" and "may include adult themes, adult activity, hard language, intense or persistent violence, sexually-oriented nudity, drug abuse or other elements, so that parents are counseled to take this rating very seriously."

An R rated movie is restricted: no one under age 17 is allowed without a parent or adult guardian.

Here is an MPAA list of movie ratings in America. You can follow the link, below, to find other rating schemes for other English-speaking countries.

This list includes the rating mark, and its description:

G	General Audiences. All ages admitted.
PG	Parental Guidance Suggested. Some material may not be suitable for children.
PG-13	Parents Strongly Cautioned. Some material may be inappropriate for children under 13.
R	Restricted. Under 17 requires accompanying parent or adult guardian.
NC-17	No one 17 and under admitted.