Every BB has a PIN number, a bunch of digits and a number. It's like a screen name that is not easily changed and is used to identify your BlackBerry in the BIS/BES.
Originally Posted by hondarider4life
The BlackBerry Messenger that is installed in your phone uses PIN numbers to send real time threaded messages between you and another person, or even you and a group. It is a very versatile and nifty bit of technology, allowing you to send HTML links, pictures, sounds and various attachments, and of course... simple text.
Think of it as an EXTREMELY exclusive AOL Instant Messenger
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