What is "DRM"? How Does it Work?

Have you ever downloaded a locked WMA or AAC file? Do you use iTunes or eMusic.com? Have you ever been stopped by your computer when trying to burn a CD? If so, then you have been dealing with DRM. "Digital Rights Management" is the padlock technology that restricts how you can download, open, install and copy digital files. But here's the problem: although you are purchasing the product, do you really "own" it when DRM padlocks are in place? Here is how DRM works, and how it has sparked a juicy controversy across the planet.