Summary

InDesign uses swatches to contain defined colors (including colors made up of other colors), tints , and gradient blends; the use of swatches lets you apply colors repeatedly with the assurance it's the same color each time, much as style sheets ensure consistent text formatting. Although you can also apply colors without using these swatches, doing so can cause output problems, especially when you're using color separations.

Key to defining colors is choosing the appropriate color model: spot or process. A spot color prints on its own plate, while a process color is separated into the four basic colors used in traditional color publishing. If you define too many colors as spot colors, you're likely to create an impossible -to-print or very-expensive-to-print document. InDesign lets you convert colors from spot to process and vice versa, so you can choose the right output options for each document. Similarly, it's best to create color images in the color model you intend to use for output: CMYK for traditional printing and RGB for on-screen display.

A powerful feature in InDesign is its ability to create gradient blends that can contain blends among multiple colors. No other layout program offers this level of control or flexibility on gradients, although image editors such as Photoshop go even further than InDesign does.