What are "web safe" colors?

When I first entered the POD arena I started reading about color shifting and the need to choose the right colors. Because I was already familiar with color in terms of designing for the web I didn't process what I was reading but instead translated it into the familiar territory of "web safe colors." That turned out to be exactly the wrong approach. "Web safe colors" are web safe meaning that they are designed for the web for a display screen, not printing and are thus RGB based. They are also a very limited set of colors, 216 of them. Many of those colors are complely outside the printable color space for CMYK.

From "Wikipedia" on Webspace colors I extract the following:

A set of colors was needed that could be shown without dithering on 256-color displays; the number 216 was chosen partly because computer operating systems customarily reserved sixteen to twenty colors for their own use; it was also selected because it allows exactly six shades each of red, green, and blue (6 × 6 × 6 = 216).

The list of colors is often presented as if it has special properties that render them immune to dithering. In fact, on 256-color displays applications can set a palette of any selection of colors that they choose, dithering the rest. These colors were chosen specifically because they matched the palettes selected by the then leading browser application

For the purposes of creating designs for print you can ignore the concept of "web safe." You need your designs to have colors that are in both the RGB and CMYK color space. Many "web safe" colors do not meet that criteria.

Image Colors

• Using the Right Colors: Understanding Color Space
• Finding CMYK colors from RGB Values
• CMYK color picker
• Is Black Just Black, and Does it Matter?