The 216-Color Webmaster's
  Palette.  This is the world's first look at the entire set of browser safe
  colors arranged symmetrically by hue. This is the set of colors most universally and
  consistently supported by web browsers.  When designing a web site, it's best to
  choose font and background colors from this set.  Also known as the web-safe palette,
  the safety palette, the universal palette, Netscape colors, dither-free colors, or the
  6x6x6 colors.
  
    
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      Soon to be available in an attractive poster, the Webmaster's Palette | 
    
  
  More info:  lab
  tour,  web colors,  CLUT (Adobe swatches),  color codes,  links
  stein@visibone.com
  Note: The color lab requires frames and JavaScript to
  interactively pick colors.  Then you can see your color picks next to each other with
  combinations of text and background colors.  On the left is the "color
  menu"  used by the color lab.  If your browser supported frames and
  JavaScript, you'd be able to hover over the colors in this menu and see the 6-digit
  hexadecimal codes on the status line.