Free VoIP softphones clients are available for download in several looks with varying features. These VoIP SIP clients (softphones) are software applications that create a virtual telephone on your computer screen to allow you to make and receive VoIP phone calls. Softphones are especially useful for people who are already using their PC much of the time or who travel using their PC for business. Softphones take advantage of your existing PC hardware to implement a VoIP telephone call and present the user with a keypad and display for placing and receiving VoIP calls. For many people having a softphone in addition to there corded phone is useful.
2 free softphones for Windows...
3CX Softphone is a free softphone for the Windows operating system created by a company called 3CX. The 3CX Softphone allows you to place calls and receive calls from your Windows computer.
The X-Lite Softphone is a free softphone for Windows that lets you make and receive free calls from your PC. The X-Lite Softphone is developed by Counterpath.
Next free softphones for Linux users.