Jiangshi are a reanimated corpse, sometimes referred to as the "hopping" vampire or zombie. They kill living creatures to take their life energy and is usually seen at night, though they are not limited to those times.
There are many different ways to become a jiangshi. Viral infection, improper death, spirit posession of a dead body, and not burying a corpse in time, among others.
They can look indistinguishable from humans, or like the typical rotting zombie.
Ways to fight them may include using mirrors (as they hate their own reflection), using vinegar, bells, fire, and oddly enough, brooms.