Level
Levels are used in all of the Pokémon RPGs as a measurement of how strong a Pokémon currently is. It is determined by how much experience that Pokémon has. A Pokémon's level will range from 1 to 100. When a Pokémon gains a level, its stats increase by a small amount. It may also learn a new move or evolve. Once the Pokémon reaches Lv.100, it can no longer receive EV points.
The level of a Pokémon will also affect breeding. Trying to breed 2 Pokémon with a big level difference will fail.
The level of a Pokémon will also affect their happiness. A level 5 Pichu will not be as happy as a trained level 50 Pichu, so the level 50 will have a better chance of evolving.
missigno, the glinch, is level 180. m' is level 0. why. because they are prototypes of real pokemon.