Working with digital images is THE most difficult area of desktop publishing to get one’s head around. It’s a very complex subject. If you’re struggling with it, it’s only natural -- everyone struggles with it at first. The subject comes with a steep learning curve.
The information below is intended for people who need to share digital images with designers, printers, or other people involved in publishing, but it's also great information for people beginning to learn about manipulating and editing images in applications such as Adobe Photoshop.