One of the commonest ways of connection to Internet is by dial up connection via a modem & a telephone line. Using these you can link to a host machine on the Internet. Once linked the telecommunications software lets you to communicate with the Internet host. While the software runs it uses the modem to place a telephone call to a modem which connects to a computer attached to the Internet.

The PPP (Point to Point Protocol) or SLIP (Serial Line Internet Protocol): two protocols; serial line interface protocol (SLIP) & the point-to-point protocol (PPP), let a user to dial into the Internet. They translate the normal telephone data stream in TCP/IP packets & send them to the network. Along with these, the user becomes a peer station on the Internet and has access to all of the Internet's facilities.