PPP (the Point to Point Protocol) is a mechanism for creating and running IP (the Internet Protocol) and other network protocols over a serial link--be that a direct serial connection (using a null-modem cable), over a telnet established link or a link made using modems and telephone lines (and of course using digital lines such as ISDN).
Using PPP, you can connect your Linux PC to a PPP server and access the resources of the network to which the server is connected (almost) as if you were directly connected to that network.
Linux PPP HOWTO document shows how to connect your Linux PC to a PPP server, how to use PPP to link two LANs together and provides one method of setting up your Linux computer as a PPP server. The document also provides help in debugging non-functional PPP connections.
