Presently, there are six different ratings for the ESRB to use: RP (Rating Pending), E, (Everyone), E10+ (Everyone 10+), T (Teen), M (Mature 17+), and AO (Adults Only 18+). There’s also an offshoot of RP reserved for games expected to be M, but it’s really no different from RP. The EC (Early Childhood) rating used to be a thing, but was discontinued in 2018.