The article http://www.symantec.com/docs/TECH213808 provides the most updated information about the predefined URL categories that are included in Symantec Protection Engine.
Table: Predefined URL categories (at the time of installation)
Symantec periodically updates the predefined URL categories. Symantec Protection Engine automatically downloads updated categories through LiveUpdate. Symantec might create new URL categories to address additional content areas as needed. New categories are not active by default. You must select the new categories that you want to use for URL blocking.
The predefined URL categories cannot be modified.
If the requested URL belongs to the CAIC category, the URL is replaced with the text CAIC-URL in all the corresponding messages and logs.
See About categories.
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