I have read many articles online about photography. But I had never actually bought an eBook on the subject until this week. The book is called Photo Nuts and Bolts: Know your Camera and Take Better Photos, launched some time go by Digital Photography School.
I finished reading it a couple of days ago. The book focuses on the camera, and how it works. It goes a bit into optics and photographic theory, and the way to understand and handle light, the basis for all photography.
It is divided into ten short chapters (3 to 4 pages each), as follows:
1. Light and the Pinhole Camera
2. Lenses and Focus
3. Lenses, Light and Magnification
4 . Exposure and Stops
5 . Aperture
6 . Shutter
7 . ISO
8 . The Light Meter
9 . White Balance
10. Metering Modes and Exposure Compensation
In my opinion, this book gives you the basic theoretical foundation so you can understand what goes on behind the scenes, and start taking better photos. Future books will go into further detail into other more practical aspects of photography.