In the twenty-first century,computer network is very important to people`s life.Especially ,to the students in the university,it is a great advantage for them to master the network technology professionally.
Network brings a great convenience to people .it is very common to do on-line chatting or on-line shopping in people`s life.Through the network,people can see the friends and relatives thousands miles away from them ,also they can buy the commodities they need without going outside...