宋曉壘

What can Internet do for us？The Internet has the following four major applications：

1. E-mail

Email On the Internet， people can compose， send and receive emails. Many people receive a dozen of emails every day， which significantly exceeds the number of phone calls and snail-paced average mails. People regard is as the major method to communicate with the outside world.

2. News

News Newsgroups are forums of limited scope where users of the same interest can communicate information. On the Internet， there are over a thousand technical and non-technical newsgroups， which cover computer， science， entertainment， politics， and other special subjects.

3. Remote login

Remote access On the Internet， the users can access the other computers that have their accounts from anywhere by using Telnet， Rlogin or other programs.

4. File transfer

File transmission On the Internet， files can be copied from one computer to another computer through FTP. Huge amount of articles， databases and other information can also be transmitted through this method.

The Network Computer

Network computer， also known as “Internet toaster”， “Internet appliance”， or “Internet device”， is an affordable and maintenance-free desktop device. The users can easily connect it with the Internet and online resources. On the desktop device， they can share any resources and complete the current computing tasks that are required to be done on the PC.

Network computer is simple in design， and all the software and hardware that makes the using of PC complicated is dispensed with. Only the network access and display functions are retained. As a matter of fact， network computer relies on the network in terms of software， services， processing， data and resources. This has eliminated the need for continuously upgrade the software and hardware of the desktop， and has shifted the burden to the network.

Do you need the latest word processing software or electronic form processing software？ Just download them from the server. Do you need to save what you have done？ You just need to upload it to the network， where it will be securely stored and backed up.

Firewall： a network security measure

With the popularization of the Internet， the security of the network becomes increasingly difficult to maintain， and the destruction of the network frequently occurs. Such destruction is brought about by the “hackers” or the legally authorized users. And the firewall is an effective measure to guarantee cyber security， and it can make sure that all the communication conforms to security policies.

Two young people once illegally invaded the network of a university， and created a bulletin board online. In the bulletin board they installed some most popular software and invited the users of the Internet to download these software packages. Thanks to the firewall， the network administrators found that the system was destroyed. They checked the audit trails， and found the IP addresses， names， and locations of these two students. The police arrested the two “hackers”.

E-mail

One important application of the Internet is that the computer users communicate with each other through emails. The users of emails can transmit and receive messages， texts， and data through emails. The email functions very like a mailbox： whether the receiver is online or not， the users can send message to him， and the message will be saved. At the same time， a signal is sent to the receiver， indicating that a message is waiting for him to handle. The transmission of message through emails has already replaced the telephone. The user can respond to it at his convenience， and will not be disturbed. He can also dispaly the message on the screen or print it.

Electronic Bulletin Boards

Another interesting application is Bulletin board system （abbreviated as BBS） which is also known as “bulletin service”. It allows the users to post or retrieve messages， which do not target a certain user. Its just like releasing notifications on the bulletin board of an office. BBS has been widely used in daily services， recruitment advertisements， and some very specialized fields， like exchanging investigation data in a very narrow scientific field.