VOIP, which stands for Voice Over IP, is phone service utilizing the internet. This is replacing the old standard referred to as POTS lines, which are plain old telephone service lines. VOIP service can work with an app on cell phones and tablets, a program on computers and/or a phone hooked up to the internet either with a cable or wifi. The phones can be moved from the office to the home or another office and one can answer and tranfer calls between phones as if they are all in the same physical location. Auto answer messages can also easily be changed from home when the weather doesn't permit you to get to the office, redirect phone calls if the internet is down, etc.