3. Image Essentials: It's All Zeros and Ones
Computers know nothing about images, or tone, color, truth, beauty, or art. They're just very complicated adding machines that crunch numbers. Every piece of data we store on a computer is comprised of numbers. All the commands we send to the computer are translated into numbers. Even this text that I'm typing is made up of numbers.
Fortunately, you don't have to learn hexadecimal or binary math to use Photoshopwe're living math-challenged proof of thatbut if you want to put Photoshop under your control, rather than flailing around and occasionally getting good results by happy accident, you do need to understand the basic concepts that Photoshop and other image editors use to represent photographs using numbers.
We'll keep it simple and equation-free (the computer does the math for you), but unless you like heavily pixellated output and wildly unpredictable color shifts, you really want to understand the essential lessons about images that we lay out in this chapter.