For photography principal I agree with other postings Understanding Exposure by Brian Peterson. An online course that looks good is at Photographylife. Look at the right side for photography courses.
To learn about your camera I'd recommend go to creative Live John Greengo goes through various cameras. I bought 2 of his courses and like them.
Losho wrote:
Can someone recommend a good beginners guide to understanding your DSLR camera? A book that covers essentials such as iso, different f stops and aperture. I'm looking for an easy to understand book that will get me familiar with a new camera, and one that explains all of the aforementioned subjects, as well as other areas of importance in photography.