The two outer radio buttons are paired to allow you to toggle between background and foreground. When you click on a color from the table it will be displayed either as forground or background depending on the state of this radio button.
The two center radio buttons above are paired to toggle between viewing the matched colors (left position) and the alphabetical list of the colors (right position).
These are the color names you can use in HTML tags anywhere a color attribute is allowed for both Netscape and IEplorer. Often it is handy to know what the actual HEX codes of these colors are if you are trying to blend them in an image. The background HEX code is shown on the left and the foreground HEX code is on the right. The decimal equivalent of these HEX numbers is also shown.
You may also change any of the numbers, either HEX or decimal, to produce your own color. TAB after you make your entry since the new color will display on the change event.