plug-ins add new features to a wiki
The functionality of a wiki can be modified or even augmented with plug-ins. These are little (or big) bundles of code that are loaded into the wiki, and there are lots of them. Some plug-ins are supported by Atlassian, others are commercially supported by third-party vendors, and still others are not supported. Not all plug-ins work in all versions of Confluence, and in rare cases plug-ins may conflict with one another, so it's best to test each one carefully before adding them to your wiki. The same is true for upgrading your wiki or individual plug-ins.
In return for being careful, plug-ins can add a lot of great features to your wiki. A good strategy is to let your users evaluate a plug-in on a test wiki before deciding to install it.
Example
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