Recent development of gaming governance requires all video games (including online games) to hold a rating label. The voluntary rating system was established by the Entertainment Software Rating Board (ESRB). A scale can range from "E" (stands for Everyone) inferring games that are suitable for both children and adults, to "M" (stands for Mature) recommending games that are restricted to age above 17. Some explicit online games can be rated "AO" (stands for Adult Only), identifying games that have content suitable for only adults over the age of 18. Furthermore, online games must also carry an ESRB notice that warns that any "online interactions are not rated by the ESRB".