VOIP technology always intrigued me, so I decided that the only was to learn about it was try it out. So started surfing the web and some of the first searches on VIOP providers brought me to:

VOIP.MS: http://www.voip.ms

Callcentric: http://www.callcentric.com

I immediately created accounts as it does not cost any thing to create one, still was not sure what I was doing.

They were throwing terms like DID (Direct Inward Dial) and Termination.

DID is an incoming line which is assigned a phone number