Ø Ability to make calls through an Internet-connected laptop when cellular service becomes unreliable or unavailable.
Ø The convenience of talking while working on a PC; the services can operate while you are doing other tasks on the computer.
Ø Advantage of price. PC-to-phone VoIP rates are much less expensive than conventional phone calls and in many cases cheaper than phone-to-phone VoIP services, which route calls through broadband modems to regular phones.
Ø Some services let you receive calls (This is ideal especially in cases where you have a permanent link like DSL or cable). In this case you can use a telephone number of your choice. You can choose a phone number from many area codes in the United States and also from several other countries.
Next : Understanding VoIP