IV
IV (abbreviation for Initial Value) in Pokemon video games (blue, emerald, diamond, etc.) - IVs are randomly generated numbers that give individual Pokemon a bonus from 1-31 in each stat. These are set bonuses that are unchangeable from the time the Pokemon is born or first seen in the wild.
Not all Pokemon are created equal. My Pikachu is better than yours because he was born with a 31 IV in speed and special attack.