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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Yahoo! Messenger is a free, advertisement-supported instant messaging client and associated protocol provided by Yahoo!. By signing up with Yahoo allows access to other Yahoo! services, such as Yahoo! Mail. Yahoo! also offers PC-PC, PC-Phone and Phone-to-PC service, file transfers, webcam hosting, text messaging service, and chat rooms in various categories.
