In role-playing games (RPG), a common method of arbitrating the capabilities of different game characters is to assign each one to a character class. A character class aggregates several abilities and aptitudes, and may also detail aspects of background and social standing, or impose behavior restrictions. Classes may be considered to represent archetypes, or specific careers. RPG systems that employ character classes often subdivide them into levels of accomplishment, to be attained by players during the course of the game. It is common for a character to remain in the same class for its lifetime; although some games allow characters to change class, or attain multiple classes. Some systems eschew the use of classes and levels entirely; others hybridise them with skill-based systems or emulate them with character templates.