If you've ever wondered about the basics of digital audio, here's a tutorial that covers it really well
Digital audio can be complicated if you're not used to the concepts you find around digital media.
Here's a very useful video that takes you through all the basics in a remarkably clear way. You still have to concentrate - this is serious stuff - but it's worth persevering.
It's presented by someone who really should know a bit about digital audio: Chris Montgomery, who designed the Ogg Vorbis codec. You don't get much more intimate with digital audio than that.
He's known for saying that there's no point (for a user) in having more than CD quality audio - because you won't hear the difference. With enourmous respect, we disagree with certain aspects of that conclusion, as we'll elaborate elsewhere (but not without first saying that to actually hear any difference, you really need extraordinarily good equipment - and listening environments).
Here's the video, and thanks to The Verge for drawing out attention to it. Note that around half way through the video, Chris moves on to digital video.