We are all busy talking about and using the Internet , but how many of us know the history of the Internet ? Many people are surprised when they find that Internet was set up in the 1960s.At that time , computers were large and expensive, Computer networks (网络) didn't work well.If one computer in the network broke down,then the whole network stopped.So a new network system had to be set up , it should be good enough to be used by many different computers .If part of the network was not working , information could be send through another part.In this way , computer network system would keep on working all the time.At first , the Internet was only used by the government , but in the early1970S Universities, hospitals and banks were allowed to use it too , however , computers were still very expensive and Internet was difficult to use.By the of the the1990s ,computers became cheaper and easier to use.Scientists have also developed software that made “ surfing ” the Internet more convenient (方便)。 Today , it's easy to get on-line , and it's said that millions of people use the Internet every day.The internet has now become one of the most important parts of people's life. 86.The Internet has a history of more than____ years.