Cave Paintings are oil paintings on cave walls and ceilings, and the term is used especially for those dating to prehistoric times. The earliest known European cave oil paintings date to 32,000 years ago. The purpose of the cave paintings is not known, and may never be. The evidence suggests that they were not merely decorations of living areas, since the caves in which they have been found do not have signs of ongoing habitation. Also, they are often in areas of caves that aren't easily accessed. Some theories hold that they may have been a way of transmitting information, while other theories ascribe them a religious or ceremonial purpose.