Definition: softphone

(SOFTware PHONE) An application for making phone calls via computer over the Internet. Known as "voice over IP" (VoIP), either a headset or a microphone and speakers are required. Softphone functionality is also available on smartphones via Wi-Fi rather than the cellular service (see Wi-Fi calling).

Softphones can work stand-alone or be part of an IP PBX family. They offer the full range of phone features, such as call forwarding and conference calling and may also interface with applications such as Outlook for automatic phone dialing. See VoIP, IP phone, IP PBX and IP telephony.

One of the First SoftPhones

Launched in 1996 with ads to support its low rates, Net2Phone was one of the first software-only VoIP services. (Image courtesy of Net2Phone, Inc.)

A Modern Softphone

This 3CX softphone is an extension on the Chrome browser. Enabling users to make phone calls directly from their computer, it is very handy for copying and pasting a phone number from a website. Clicking the 3CX icon on the toolbar opens this dialog to make an IP phone call. See browser extension.