WebSkins technology allows you to customize the entire look and function of your forums and integrate them anywhere into your site. Many example skins are available to tinker with and modify for your own needs. A JSP tag library makes creating brand new skins easy. Message content is dynamically formatted by any number of filters. Examples of filters include syntax highlighting of Java code, translation from one language to another, and getting rid of those naughty words that little Johnny shouldn't see.
Third parties can easily create and distribute their own filters.
The filter system coupled with WebSkins makes Jive truly extensible. Cache settings are adjustable to tune for maximum performance or minimum memory usage. Jive's open and well-documented API's make it easy. Search settings are fully adjustable in the admin tool. Security Permissions for reading forums, posting threads, and posting messages are fully adjustable on a per-user basis.