For our content we use the ESRB Ratings Guide. When filling out the submission form for your content, you will have an opportunity to rate it, as well as to included content warnings.
Here is a basic overview of what the ratings means:
T for Teen: Content is generally suitable for ages 13 and up. May contain violence, suggestive themes, crude humor, minimal blood, simulated gambling, and/or infrequent use of strong language. This is the default rating for everything, as World of Warcraft is a T-rated game.
M for Mature 17+: Content is generally suitable for ages 17 and up. May contain intense violence, blood and gore, sexual content, and/or strong language.
A for Adults Only 18+: Content suitable for adults ages 18 and up. Maybe include prolonged scenes of intense violence, graphic sexual content, and/or gambling with real currency.
For anything beyond a T rating, you must include content warnings, which will most likely be one of the following:
If none of these fit, or if you have other or more specific content warnings you wish to include, you can do so in the "Additional Content Warnings" section of the submission form.