Whas is the main purpose of all computers ?

Nowadays computers play an important role in our life.One can see computers and computer devices in every home.Is it right?well, i think the answer is not easy to get. People got used to computers as far as they need them not just for work, but for communicating also. Internet has occupied the lives, everyone is surfing for some music or video, or just chat. I guess, there are a lot of useful work computer an do.But we also have to remember that spending hours in front of screen is very harmful for our health. So, i personally think that computers are valuable contribution to peoples' life