EVs, or effort values, are earned through battle or vitamins. Each Pokemon has a set of "EVs given." Usually it's 1-3 of the same stat EV, but sometimes it's split between two or three. For example, if you defeat a Blissey, your Pokemon will get 3 HP EVs. If you defeat a zubat, you will get 1 Speed EV.

Evve

EEVEE!!! 💓💓