Also called "Chat Programs". These applications are installed on a PC by a user, and allow immediate "chats" between other users of the program. Some of these programs also allow audio or video conferencing as well as the ability to execute file transfers.
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If you're looking for the most user-friendly instant messenger client to talk instantly in real-time using the Internet, Freo is one of the best options available - a totally free and clean Windows multi-capable instant messenger client.
