Voice over Internet Protocol (VoIP),
is a technology that allows you to make voice calls
using a broadband Internet connection instead of a
regular (or analog) phone line.
Some VoIP services may only allow
you to call other people using the same service, but
others may allow you to call anyone who has a telephone
number - including local, long distance, mobile, and
international numbers.
Also, while some VoIP services only
work over your computer or a special VoIP phone, other
services allow you to use a traditional phone connected
to a VoIP adapter.