Zombies

Official Description
"These undead husks of former humans, possessing no living functions, feeling no pain and following no reason are driven solely by most primal need of eating flesh. No one knows how they came to existence. Some believe they're created via necromancy and dark magic, while the more reasonable people argue they're a gut-wrenching result of use of biological weapons during the Last World War. Even though since the 2140's no occurrences of people returning as zombies after death have been noted, the belief in a "zombie virus" still prompts people to burn the deceased instead of burying them. Contrary to the common superstition, zombie bites don't cause the victim to turn, however they're still dangerous due to abundance of germs and bacteria carried by them. Due to their impaired motoric functions, Zombies pose no direct threat to humans, but many perceive them as pests, as their rotting bodies tend to spread diseases wherever they go."

Trivia

 * Zombies come in different variations.
 * They will NEVER be sentient, as their brain has rotted away.