All Games on Should Be Rated

Honestly, in my opinion, there should be a rating (i.e. All Ages, 10+, 18+, etc.) or content descriptions (Fantasy Violence, Mild Language, Rude Humor, etc.) for younger audiences. A child may not know if what he/she is playing is violent or has language.
Maybe the community could rate it, or the maker themself.
This is just an idea, though.