There is a third way of delivering information, which uses the Internet.

The Internet is more like traditional telecommunications in that Internet connections are normally one-to-one. Internet is unlike telecommunications in that your link to a Web site (say), as you browse, is connectionless.

Data from the home page that you reach are broken down into packets at the server. Each packet is about one thousand bytes long. Each packet is put into an ‘envelope’ (which adds a few more bytes). The envelope has extra items of information, like the address of the machine from which the packet is sent, and the address of the machine to which it should be sent.

You can think of the Internet as a collection of static postpersons. Each postperson reads the address on the envelope, and passes the envelope on to the next postperson. The postperson is quite intelligent. Reading the address on the envelope she knows which postperson would be a good choice for next along the line. Also, if the obvious choice of next postperson is overworked, she can make an alternative choice of next postperson.

The postpersons in Internet are computers called routers. The protocol which breaks up files into packets and labels and delivers them is called Internet protocol. Files are passed around the Internet in these broken down pieces, and so the Internet is robust if some bit of the network ‘goes down’, unlike the telephone network.