Voiceover IP Guide - Skype
Skype was founded in August of 2003 by the clever guys behind the infamous Kazaa peer-to-peer file-sharing programme. Skype is claiming to be the first genuine peer-to-peer telephony program. The technology behind Kazaa that made it so successful (and resilient to legal actions) is being used to power voice calls over the Internet.
What makes this method different is that it does not use a central server processing user data and connection information. Each PC running the Skype application becomes a node in a huge network of Skype users who share the load of operating the system. The shared information database is required to keep each user informed of who is online at any given time. Calls can also be routed through other Skype 'nodes' when direct communication is unfeasible.
The idea of Skype is to have a self-maintaining network of users, who can communicate with each other by voice for free just as they would communicate using an instant messenger program like ICQ. This is free global telephony leveraging the power of broadband internet to allow users to make unlimited, quality voice calls via peer-to-peer software. Distance and location are irrelevant as long as you are connected to the Internet. There are no costs or time limitations attached to calling. You have 'buddy' lists just like ICQ or MSN, and can search the Skype database for people to contact.

