When you create something, you as the creator possess ownership of what you created. This ownership is covered by various definitions from copyright, trademark, patent, etc. Some of these you need to file paperwork for, others not necessarily as long as you can prove you created it before someone else if asked later. You own that "copyright" until you transfer it via license to another person. You can transfer it permanently or temporarily, with or without restrictions, for money or not. Royalties, Royalty Free, Creative Commons and so on are all just variations of what is referred to as a "license to use".
For example, Creative Commons Attribution (3.0 unported) states that you can copy, distribute, perform and display the work as well as making derivative (usually defined as a product with added value of some kind including the original work) AND most important you can do this in a commercial capacity, making money from the song. BUT there is one condition. You must in every single instance that the work is used, properly credit the original creator. When people mis-use the term Royalty Free and talk about non-copyright, Creative Commons Attribution is what they need.
Royalty Free on the other hand always has a cost associated with it. Yes, technically a song under CCA above is also Royalty Free, but they're never advertised that way. Usually for Royalty Free you'll pay between $20 and $400 for a song depending on what you want to do with it. And once you have paid that money, you have a perpetual license for that product without any additional burden of cost. Most also don't require giving the original artist credit of any kind.
