Stone-age literally means something from the longest period in the history of man, that time which is shrouded in the ages, when only stones were used for tools. The term has also come to mean anything primitive or antiquated, it suggests we have come up with something much better since.
Stone-age Man is a mystery to us. The typical image is a fur-clad maniac with a limited vocabulary who hits dinosaurs over the head and drags his woman home by the hair. Since the large dinos had died out by the time Man and his relatives came to, this notion is decidedly untrue, but for the others we cannot say it was one way or the other. Language must have been an infant once, too. Women in the stone age may have been disrespected or worshipped, no stone slab feminist tracts remain to tell us. We do not know what stone-age people believed in or what they did for amusement, although fragments from the past allow us to guess.
We can imagine, but we can never know exactly what it was like to live in prehistoric times. In the same way, thinking back to the time of the first computers which we now find laughably slow and simple is quite impossible to us. Think of what an achievement it really was. Think of what it brought.
Stone-age tools are considered simple precursors to what came later, and the art naive and basic. Yet they came out of nothing. Without stone-age development, there would be nothing to come afterwards. Our net and phones and databases are surely the stone-age artifacts of a future age.