Royalty Free: does not mean that the media is free, or in the public domain. It means that you can use the media (under whatever license it is offered under) with out paying Royalties (additional costs for additional uses/performances/etc.) after the fact. Some Royalty Free materials ARE offered for free use, but the copyright holder retains all rights. Some are sold for a one-time fee.
- standard introduction?
-topic specific guidance?
-figure out how not to have it at all? (if so what does the user "land on")