First things first, VoIP stands for Voice over Internet Protocol. At a base level that means phone calls over your broadband connection. You really do need a high-speed connection to take advantage of VoIP to get phone calls comparable to a normal landline phone. Traditional "dial-up" connections are not really sufficient.
VoIP works in a different way to your home phone. Your home phone is based on an analogue network, whereas VoIP is based on a digital one. Essentially when you speak into a VoIP enabled phone or headset your voice is converted into digital packets; it is then compressed to help your Internet connection run more efficiently and then it is transferred down the connection much like an email. Once it reaches its destination the process is reversed.
Why might I want to switch to VoIP?
It's a good question. We all have a working phone in our homes or business, why should we change? Lets look at the advantages and disadvantages of VoIP
Well to put it simply - cost. VoIP makes calls significantly cheaper. And (Depending on your package) for a low cost monthly subscription local and national calls can be made for free, and international calls made at a significantly lower rate.
When you subscribe to a VoIP service it is possible to get a phone number for life. You will be able to take your number with you whenever you move (or even travel) with obvious benefits.
The contract packages that companies who are offering the service contain for the most part all the features and more that your current phone service supplier offers. You are likely to find most VoIP companies offering free voicemail, call forwarding, caller ID, call waiting, call waiting ID, 3 way calling, speed dialling and much more.
VoIP is very much in it's infancy; the technology is progressing all the time. Future benefits that we may not be able to envisage yet are certain to appear, you current analogue phone system will not be able to compete.
Your VoIP phones system will be exclusively based on your broadband connection, if you ISP has a period of service downtime then you will not be able to make calls. Additionally if your electricity supply has a power out then you will not be able to make any calls, this includes calls to the emergency services. Some providers have already got a work around with the emergency calls, so make sure when you decide on a supplier they provide this.
A further disadvantage currently is the set up of the VoIP is not the simplest procedure to undertake, though many suppliers will assist with installation.
The quality of the call via VoIP can be slightly less than your current analogue phone, but the technology is steadily improving, and before long you will not be able to tell the difference in call quality between the two mediums.