A lot of Haitian and West African voodo believe that a spirit or spell can bring a corpse back to life.
In August 1996, National Geographic magazine reported that men of Togo, West Africa chanted a blessing over sacred knives which were then pointed at chicken which then shivered and died without being directly touched.
Also, there are proven cases of voodoo zombies which are people who are brought to the brink of death using a certain substance that lowers your breathing and heart rate by the witch doctor. They are then buried and dug up soon after and revived by the doctor however they either have long term brain damage from the lack of oxygen and the drugs, or they die.
The ones who survive are often sold on by the witch doctor and because these peoples brains have been so badly damaged, they only function on basic commands.
A lot of stories about zombies say that they are undead beings who feast upon human flesh and organs.
Their weaknesses are usually a bullet or bash to the brain and to be contaminated, you should avoid being bitten by a zombie, or mixing bodily fluids such as blood or saliva. After a period of time of being a zombie, their flesh starts to rot and fall off because of the dead vessel they are using, so this gives them a bloody gory effect.