A caveman is a based upon widespread but anachronistic and conflated concepts of the way in which Neanderthals, early modern humans, or archaic humans may have looked and behaved. The term originates out of assumptions about the association between early humans and caves, most clearly demonstrated in cave paintings. The term is not used in academic research.
Cavemen are typically portrayed as wearing shaggy animal hides, and capable of cave painting like behaviorally modern humans of the last glacial period. Anachronistically, they are simultaneously shown armed with rocks or cattle bone clubs, unintelligent, and aggressive. Popular culture also frequently represents cavemen as living with or alongside dinosaurs, even though non-avian dinosaurs became extinct at the end of the Cretaceous period, 66 million years before the emergence of the Homo sapiens species.
The image of them living in caves arises from the fact that caves are where the preponderance of artifacts have been found from European Stone Age cultures, although this most likely reflects the degree of preservation that caves provide over the millennia rather than an indication of their typical form of shelter though Neanderthals never lived in caves. Until the last glacial period, mosthominins did not live in caves, being nomadic hunter-gatherer tribes living in a variety of temporary structures, such as tents (see Jerry D. Moore, "The Prehistory of Home", University of California Press, 2012) and wooden huts (e.g. at Ohalo). Their societies were similar to those of many modern day indigenous peoples. A few genuine cave dwellings did exist, however, such as at Mount Carmel in Israel.