Rating

Rating 

Refers to a classifcation system in which a story is marked for suitablity by age or content. Rating levels indicate what amount of graphic language, violence, or sexual content a reader might anticipate within the story. Most fanfiction ratings still follow the USA Motion Picture Ratings established for television and movies, whereby G=General Audiences, PG=Parental Guidance, PG-13=Parental Guidance for Anyone Under 13, R=Restricted to Mature Audiences Only, and NC-17=No Children Under 17 Permitted. However there are a growing number of sites now using the non-copyrighted Fan Rated Rating System with its equivalent values, and some other sites that use their own personal systems. 

Fan Rated Rating System☟︎︎︎http://tfrrs.tripod.com/