Based on the 1954 novel by Richard Matheson, I Am Legend is the story of Robert Neville (Will Smith), the last man living on Earth, with some zombie-vampires thrown in for action.
In Haitian and African folklore, dead people can be revived - thus their corpses reanimated - through spells, witchcraft or Voodoo. Similarly, a zombie-like state can be induced through various pharmacological means so that the person falls into a deathlike state and is pronounced dead but reawakens sometime later - such as after being buried. In fiction, zombies are portrayed as soulless walking dead who feed on brains (Return of the Living Dead) or human flesh. Read articles about zombies below.
If you’ve never thought to deeply about zombie movies, you may want to read Discover Magazine’s article on what you can learn from them.