Skype lets you make free calls to any other Skype user from your PC. Initially dismissed by the big VoIP (voice over Internet protocol) providers as nothing more than an interesting blip on the telephony radar screen, it has more than proven its mettle. Skype, a free P2P VoIP application, has more than 29 million registered users worldwide, with an average of two million using the service at any given time. Perhaps more significantly, SkypeOut, the company's first premium service allowing users to make calls to regular telephone numbers, has surpassed one million subscribers since its introduction in July 2004.

Skype is a valid alternative to archaic landlines' per-minute long-distance charges or the restrictive contracts and steep overage charges of mobile phones. But the idea of using a PC to make telephone calls is overwhelming for some.

This guide shows you how to get the most out of Skype. Whether you're a new user or a seasoned pro, you'll get more from your service with these simple tips. We'll begin with a quick tutorial on how to set up Skype and make your first calls. From there, you'll learn many of Skype's more advanced features, including calling regular phone numbers, using headsets, and hooking up external gear like PDAs or smart phones.