Gym

Gyms are locations triners can conquer by fighting the Pokémon(s) set there to defend it by trainers from other teams.

After conquering a Gym a Trainer can leave only one Pokémon there to defend it. That Pokémon is not acessible to the trainer while it is there.

If a gym belongs to someone of the same team you can add one of your Pokémon to it.

Every 24 hours a Trainer can collect a defender bonus that depends on the amount of Gyms owned. Gyms you added Pokémon to help defend also count for this bonus.