Different types of Instant Messenger:
ICQ- a combination of letters that is shorthand for the phrase "I seek you," is a real-time tool that uses a software application, called a client that resides on your computer. The client communicates with an ICQ server whenever you are online and the client is running
AIM- uses a proprietary protocol that is not understood by other instant-messaging services. A key reason why AIM is so popular is that it allows AOL members to communicate with non-members.
MSN- Microsoft's MSN Messenger, like other IM programs, allows you to talk with another MSN messenger user just like you would over the telephone. You and the person you wish to talk to must each have a sound card, microphone and speakers to use this feature.
Yahoo- Another instant messenger service that integrates your yahoo account with other Yahoo! content and services.
Odigo- allows you to combine AIM, ICQ and Yahoo! Messenger contact lists. Omni lets you combine the functionality of AIM, ICQ, MSN Messenger and Yahoo! (How Stuff Works)
These are just a few major companies of instant messaging services, but there are still several others.
Businesses use of Instant Messengers
Instant messaging in classrooms
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