Adobe Lightroom is the state of the art for non-destructive photo editing.
Unlike Photoshop, Lightroom never touches the original image. Instead, all edit instructions are stored in the Lightroom Catalog, and can be changed at any time. When an image is produced (for example, by printing it or sending it to email), then all the editing instructions are applied and the final image made.
This approach, called metadata editing, means we can change our mind at any time, nothing is fixed and no changes we make are permanent!
Lightroom manages all your images in one place (called a catalog), lets you ‘develop’ the image for best effect and then make a slideshow, a web site, or print our masterpieces.
I can teach you how to set up and use all aspects of Lightroom on either Mac or Windows based machines. If you prefer you can use machines in my studio, but usually working on your own images on your own machine is the best way to learn.