The Outbreak; The outbreak begins as a disease, a quickly spreading virus that if you're lucky, won't be airborne. The disease is quickly spread, through saliva or overall bodily fluid contact.....that's right, beware of the zombie semen, and the symptoms that this outbreak would entail would be a high fever, people would start shivering and sweating profusely, they would grow pale in color and they're body would turn cold. Coughing, bleeding from the orifices(especially nasty), delirium, stiffness of the body...these are all sure signs that the person has been infected by the Z-Virus(I know it's a stupid name but for the sake of the argument just go with it) This is the most common conceptions of how the Zombie Apocalypse will begin.
The viral weapon; This one is all about government conspiracies, let's just say(and I'm not saying it) that a certain government from a certain country, might or might not be perfecting viral weaponry that they might test on their citizens, if such a thing were to happen you KNOW that they'd get their hands on there quick, probably killing everybody to bury the evidence but again, that might or might not happen but remember that you didn't read about it here!
The Rage; These are not actual zombies but they have the same overall effect, these are people who have become sick which makes them highly volatile and dangerous. This one is also a disease, spread through contact with fluids so again, beware the........you know....
The Voodoo; This one is just plain magic so in my thoughts this is the least likely to occur, probably some pissed off broad wants to get back at her man for cheating on her so she picks up a voodoo book that her mom gave her for christmas and voila, she sees a spell for reviving the dead so she decides that she'll scare him. Needless to say she loses control and dooms us all....damn broads. These type of apocalypse is different in the fact that the dead actually come back to life, meaning that its not a virus but that the dead ACTUALLY come back to life so a bit or a scratch is no concern and the only thing you'd have to worry about is an infection.
The Actual Apocalypse; We'll here we're pretty much fucked since well, its an actual apocalypse. The dead would come back to life and they would be more than the living etcetera etcetera...you know, biblical stuff.
So here you go, hope you enjoyed the list and remember to comment with any suggestions you might have!
Also, If you haven't watched Shaun of the Dead then do so since it shows the funny side of the zombie apocalypse...