They are all the same thing. Simply put, it is just making your phone call over the Internet for at least half the cost. Internet phone (VoIP) has come of age and if you have high speed Internet service in your home, there is almost no reason not to have Superior Internet phone service. It is all digital , so, the calls are clearer and the cost is not even comparable. You can talk all over the U.S. and local unlimited for the same lower fee every month. There are no gimmicks with VoIP, even fees and charges you would pay with a normal land line are excluded, making the service even cheaper. All one pays is a small federal excise tax, see the chart below.

Unlimited Local and Long Distance - Unlimited Calling to the U.S. and Canada
FREE Second Line - Have two calls at once with the same number
Keep Your Number - Transfer your number for FREE or get a new number
30+ Features Included - Voicemail, Caller ID, Call Forwarding
Why switch to a VoIP solution?
VoIP Phone Services are cheap, easy to setup, and it is for everyone! The cost savings advantages are amazing if you are a large volume caller and still good even on an average residential phone service. With all the additional charges on a local/long distance phone provider, here is an excuse to get out of them. Broadband phone is an emerging technology and none of them apply. Look at your phone bill itemization and you will understand what I mean.
I've used several VOIP phone providers in the past and this one has been the best. I used Sun Rocket and after they went out of business, tried one that didn't end up being very good. Signing up with Phone Power has been a pleasant surprise. My online order was processed quickly, the equipment came soon thereafter and I had no problems setting it up. I am very pleased with the quality of the phone lines and all the features that they offer. So far, Great! I highly recommend Phone Power VoIP and with the second line free deal it is hard to beat. Telecoms Sale - Blog Owner