Softphone
A software application that allows a computer to be used to dial numbers, make phone calls, and perform other functions that a traditional phone would be capable of doing. A softphone combines a software program that operates on a computer along with a signal processing card (a sound card) to provide telephone services. A firmphone relies on its own circuitry for the telephone signal processing so that it does not burden the computer's operating system when processing the call. More importantly, if the operating system is busy servicing other software applications (such as a word processor), it does not degrade the quality of the telephone call.