Some of the most powerful tools in Photoshop are the Selection tools. They enable you to edit selectively as well as create interesting effects with the Transformation tools.
Try to develop a feel for when you can use selections. They can save you a great deal of time when you need to fill a space with color or an image, when you need to manipulate just a piece of an image, when you want to selectively brighten or adjust part of an image, or when you need to extract a piece of an image from a larger work.
We will refer to selections throughout the remainder of the book, so if you need to, dog-ear a page.