I use Photoshop almost every day, preparing the images that appear in OGR magazine. It is the “800 pound gorilla” when it comes to image retouching and manipulation. However, it is SO capable and can do so many things that is has a very long learning curve.
If you are seriously considering getting this program (or one of the less costly clones) I would suggest you get the “Photoshop for Dummies” book. The “dummies” series is well written and easy to understand. I have several of the “dummies” books for various software in my library.