From Halopedia, the Halo wiki
ChatterNet is a communications network that once played a vital role in everyday human life, but has seen diminished use by the 2550s. By 2558, some thought of ChatterNet services as something one would expect to see in prevalent use fifty years ago. "ChatterNet" usually refers to a network localized to a specific world, but it can also be applied to all the networked information stored across all of them that exist. ChatterNet is considered very secure, when compared to similar tools such as Waypoint. It is often used by individuals wishing to keep their activities clandestine. For this reason, one of its primary uses concerns the making and tracking of financial transactions. As secure as it is, however, it is not impregnable. Experienced hackers regularly break into chatter lines through a process called "ghosting," permitting them to spy on the activities of users or to steal their identities without attracting attention. Such a breach of protocol is highly illegal. The ChatterNet at-large is maintained and policed by the Chatter Protocol Authority.
Named for the large communications network, a chatter is a small computer, typically worn on the wrist. Chatters can access the ChatterNet and also contact other chatters and their users, as well as keep calendars and store files. Novelty shops often sell disposable versions for those who are unable to afford regular service.
As of June 25, 2015, 343 Industries' Jeff Easterling created "Canon Fodder: ChatterNet", a series of forum posts on Halo Waypoint in which Easterling asks fans questions relating to the Halo universe and features some responses on the following week's issue of Canon Fodder.
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