Basically the shout box is a mixture between a graffitti wall and a chatroom, is like a chatroom where messages are refreshed only reloading the page. Basically users can send messages to the shout box and the last "n" messages are displayed. That's all, pretty simple.
In Tiki you have a two-way shout box, you can use the shout box screen and you can also use the shout box module.
The shout box screen
The shout box screen can be used to enter messages display the last "n" messages and if you have the permission edit or remove existing messages, the shout box screen is the following one:
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The shout box module
The shout box module is more interesting because it can be used as a normal module following the user across all the site sections. The shout box module is similar to the following:
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Optional parameters
tooltip=1 - displays the time of a post in html tooltip (title attribute) instead in the content of shoutbox
Users can send messages, see the last "n" messages ("n" is here the number of rows for the shout box module) and if you have the permission you can remove messages or edit existing messages (will take you to the shout box screen).
Permissions
The following permissions can be used to control the shout box: