There are basically two types of VOIP plans. One plan allows you to use your computer as a phone, with a headset or even a plug-in telephone. These services are very low-cost -- some even close to free. And they can be very convenient for business travelers who can talk through their laptop connections. But these plans do not allow you to use a traditional phone. If you want to use your current phone -- and number -- with VOIP, you will need to purchase a phone-based plan, which is more expensive, but is comparable to service from a land line.