According to Wikipedia cave paintings are a type of parietal art (which category also includes petroglyphs, or engravings), found on the walls or ceilings of caves. The term usually implies prehistoric origin, but cave paintings can also be of recent production: In the Gabarnmung cave of northern Australia, the oldest paintings certainly predate 28,000 years ago, while the most recent ones were made less than a century ago.
I see these early forms of visual communication as a vital part of human evolution. Who knows where we would be now if we hadn't started drawing on the walls of our caves.