About color modes and models (Photoshop)
A color mode determines the color model used to display and print images. Photoshop bases its color modes on established models for describing and reproducing color. Common models include HSB (hue, saturation, brightness); RGB (red, green, blue); CMYK (cyan, magenta, yellow, black); and CIE L*a*b*. Photoshop also includes modes for specialized color output such as Indexed Color and Duotone. ImageReady uses RGB mode to work with images.
In addition to determining the number of colors that can be displayed in an image, color modes affect the number of channels and the file size of an image.
You can set up the Info palette so that you can select any tool, position the pointer over any part of an image, and determine the color value under the pointer. You can customize the Info palette and color samplers to express color values using HSB, RGB, CMYK, Lab, or Grayscale modes without changing the mode of the image itself. (See "Seeing the color values of pixels (Photoshop)" on page 133 and the procedure to change Info palette options in "Using the Info palette (Photoshop)" on page 32.)
Adobe Photoshop can be a complex tool only because you can do so much with it, however for in this video series, we're going to keep it as simple as possible. In fact, in this video you'll see an overview of the few tools and Adobe Photoshop features we will use. When you see this video, you'll see how you can do so much with so few features, but you'll learn how to use them in depth in the future videos.