(First of all, if this has already been suggested/implemented I apologise for wasting your time. I also apologise for the terrible explanation you're about to read... >.> )

EVs (Effort Values/points) - Points which pokemon gain through battling or the use of items. These points influence a pokemon's stats (Attack, Sp.Attack, Defence, Sp.Defence, Hp and speed.) E.g. If one's pokemon were to fight Zapmocluno's Zapdos, one's pokemon would gain 3 EVs in sp.attack (Each pokemon give a different amount of EVs in different stats)

A pokemon's stats can also be influenced by items such as Protein Zinc, etc. Each of these items give 10 EVs (To their respective stats.)
They can also be influenced by held items (Included in the serebii link below)
(There's more but, since anyone who's read any of my previous suggestions knows, I am absolutely terrible at explaining things! So I'll just leave a link to serebii. Everything I've mentioned and more is elaborated in (better) detail there.)
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