PC-Telephone® is a powerful communications software application that enables you to exploit the full communications potential of the Internet and public telephone networks ISDN/PSTN. PC-Telephone makes possible to use your computer as Internet telephone, ISDN phone, fax machine, voicemail and much more. Use PC-Telephone to place unlimited, free PC-to-PC and cheap PC-to-Phone/Fax calls over the Internet/Intranet and ISDN/PSTN telephone networks. PC-Telephone is the first software application that integrates the regular Computer Telephony and Internet Telephony (Voice over IP) in a single user interface.