IVs are known as Individual Values. They are random numbers given to a Pokemon in each stat. They are capable of increasing a stat of your Pokemon. The highest an IV is 31, which is considered to be 1 IV. If all of the stats (HP, Attack, Speed, etc.) had 31 IVs, it'd be known as a 6IV Pokemon. IVs do more than that though! They determine Spinda's spot pattern, Wurple's evolution, and what hidden power type you have!
However, IVs are completely random when you find the Pokemon in the wild. To get good IV Pokemon, you could find a Ditto from a friend that has 6IVs. They're floating around everywhere here on Pokemon DB. Give it a Destiny knot and breed it it the Pokemon you want to have good IVs.
In order to get good IVs on a breeded Pokemon, the other parent is recommended to have high IVs as well.