Nope. EVs is short for Effort Values. It's a term used around the community to refer to the hidden points earned while training a Pokémon by battling or by giving Vitamins. Each Pokémon you beat, be in the wild, owned by a Trainer or any possibility provides another set of points besides Experience. You can't see those points, but they accumulate in your Pokémon's Stats.
For example, if you beat a Rattata, you'll get 1 Speed Point for your Pokémon's Speed Stat. All other Pokémon give different EVs depending on their Stats. The points they give can be checked in any Online Pokédex.
Vitamins are worth 10 Effort Points for the particular Stat. You can feed up to 10 Vitamins per Stat, which equals 100 Effort Points at such Stat. Each Stat can get a max of 255 EPs, but since each 4 EPs equal 1 Stat Point in the final rundown (Level 100.), the actual max for the Stat is 252 (63 Stat Points.).
In the 3rd Generation Games, there's a cap for how many EVs can a Pokémon get. The cap is 510 EPs, which is roughly 2 maxed out Stats. Considering that to max out the Stat Points you just need 252 EVs, you can have 6 EPs to spare and give 1 extra Stat Point to any Stat you desire. There are more advanced EV spreads for Pokémon, but that's achieved through testing and such.
In short, EVs are the hidden points that puts apart wild and trained Pokémon, and improve the Stats of your critters.
