Where can I find documentation on functions such as

    $category->hasChildren()

...or..

   {{$count = $RecordsClass::contentCount( $category, FALSE );}}

When I google for, say, "IPS Community contentCount", I get very little.  What documentation do I need to read to understand what functions are available?  I'd like to, for example, get all articles for a given category, but I can't figure out how to do so.

Thanks,
Bret

hasChildren() is documented here: 

 

To get all articles in a category, you would use getItemsWithPermission() documented here: