Zombies are a mutated form of Humans or even Anybody. Zombies are so evil, they munch on your arms and turn you into one. There is lots of zombies in Raccoon City and in Call of Ducky: Black Ops. Chuck Norris and Bowser can't get turned into a zombie because they are just plain awesome and undefeatable. Also, Frank West became famous from killing lotsa Zombies.
Zombies can get killed really easily, by using a Shotgun, Magnum or a Pie. People can throw things at zombies, and they just die. Chuck Norris is a trained zombie ahnillator, with his BFG armed and ready to deploy several bombs, and now zombies die from looking at him cause the zombies are so scared of him.
The Zombies in the pic aren't really Zombies because they are not green and they are naked (Not like in da nude naked, I mean like no skin), and don't forget that they don't look like green, blood splattered humans. Real Zombies look unique compared to others.
The easiest way of killing zombie is planting some plants in your backyard.