RPG stands for role-playing game. It is a game where participants typically assume the role of fictional characters.
RPG was created on USA by the end of the 70s and it became very popular, specially due to its appearance on the movie ET and the cartoon Dungeon & Dragons, based loosely on a RPG published by Wizards of the Coast (formerly TSR).
In the past, the church has been against RPG, even claiming it was satanic. However, as usual, God's wisdom enlightened his followers and the church has accpected RPG as just your average sunday game.
There have been instances of RPG players killing each other during sessions, doing drugs and performing devilish rituals; these, however, were seen as isolated events and the game is thought to be good for making friends, learning history and improving memory skills.