First, I'd like to say it's ridiculous that people think zombies are real.  The modern zombie was not created by Robert Kirkman of the Walking Dead.  The modern zombie was created by George Romero, so when people talk about preparing for the zombie apocalypse, I tell them they're morons, because zombies aren't real, they were a figment of Romero's imagination.  Actually, you can trace the modern zombie back even farther and argue that it was created by Richard Matheson.  Allow me to explain...

The first zombie movie was 1932's White Zombie starring Bela Lugosi.  In this, and other zombie films of the era, zombies didn't eat the flesh of the living, and if a zombie bit you, you didn't turn into a zombie.  Early zombies, like in White Zombie, were more slaves than flesh eaters.  That's the early zombie in a nutshell.  Now, in 1954, Richard Matheson wrote a novel called I Am Legend about a virus that turns everyone into vampires except one man (I Am Legend was the basis for Vincent Price's Last Man on Earth and The Omega Man starring Charlton Heston).  Now, George Romero got the idea for Night of the Living Dead from I Am Legend.  George Romero, and fellow writer John Russo, came up with the idea of the dead coming back to life, eating the living, and turning the newly bit into flesh eating zombies.  So...there's no such thing as zombies.  Take that stupid "preparing for the zombie apocalypse" sticker off your car.

Oh yeah, and zombies don't run, they walk.  How can a recently reanimated corpse run?  That's stupid.  So is the remake of Dawn of the Dead and all the other zombies movies that followed suit.  So, George Romero invented the modern zombie and he took it a step further with the Night sequels, Dawn and Day of the Dead.  Here's a little lesson in Dawn of the Dead:

Dawn of the Dead was produced by Italian horror legend Dario Argento.  Dario took Dawn and recut and rescored it for the European audience and renamed it Zombi.  Now, all of Romero's zombie films have some sort of social commentary, in Dawn of the Dead, he focuses on consumerism, that's why the film takes place in a mall.  Argento's Zombi, is a much darker film that does lose some of the social commentary, but it's still a great cut of the film.

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Zombi was a huge success in Europe and Italian filmmaker Lucio Fulci wanted to capitalize on this and made an indirect sequel called Zombi 2.  Zombi 2 was released in England as Zombie Flesh Eaters and in America as Zombie.  In Dawn of the Dead, we saw recently reanimated corpses come to life to eat the living (at this point I'd like to point out Tom Savini's amazing special effects in this and Day of the Dead).  In Fulci's Zombie, the zombies that came to life were recently deceased, but he also brought back 400 year old corpses to reek havoc.  That's where decrepit, rotten zombie comes from!  And if you're a 400 year old zombie, can you run?  No!  So zombie's don't run, zombie's walk.

So, there's your shotgun lesson in zombie cinema.  And what have we learned?  There are no such things as zombies and if you're preparing for the zombie apocalypse than you have way too much time on your hands.