On these fora, there are many questions on DVD-Video. What it is, what it isn't, types, limitations, and the list goes on.
Jim Taylor, author of DVD Demystified, tells you everything in his wonderful book. He also has a DVD FAQ page, that covers most of the main parts of his book. While I highly recommend the book (should be in any video editor's library), some times people only want to learn of a specific topic. Mr. Taylor makes that easy.
DVD Demystified, Jim Taylor, Mark R. Johnson and Charles G. Crawford, McGraw-Hill, ISBN 0-07-142396-6. I have the Third Edition, but there may be newer releases.
If it involves DVD-Video (or BD, or even CD), his book will give you all of the answers.