I visited the largest Chinese cemetery in Southeast Asia today. In Chinese theology, a person has two souls. The yang soul resides with the living and dwells in the family home. The yin soul because it is seen as potentially dangerous and must be pacified and kept away from the family.
Once a year in Ching Ming Chinese people visit the grave site to clean it, make offerings and burn cardboard replicas if luxury items (cellphones, cars, money etc) to send it to the spirit world and pacify the spirits.