(*^

::[	frontEndVersion = "Macintosh Mathematica Notebook Front End Version 2.1";
	macintoshStandardFontEncoding; 
	paletteColors = 128; automaticGrouping; currentKernel; 
	fontset = title, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, bold, e8,  24, "Times"; ;
	fontset = subtitle, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, bold, e6,  18, "Times"; ;
	fontset = subsubtitle, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, italic, e6,  14, "Times"; ;
	fontset = section, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, grayBox, M22, bold, a20,  18, "Times"; ;
	fontset = subsection, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, blackBox, M19, bold, a15,  14, "Times"; ;
	fontset = subsubsection, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, whiteBox, M18, bold, a12,  12, "Times"; ;
	fontset = text, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = smalltext, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  10, "Times"; ;
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	fontset = message, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, R65535, L-5,  12, "Courier"; ;
	fontset = print, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, L-5,  12, "Courier"; ;
	fontset = info, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, B65535, L-5,  12, "Courier"; ;
	fontset = postscript, PostScript, formatAsPostScript, output, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeGraphics, M7, l34, w282, h287,  12, "Courier"; ;
	fontset = name, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7, italic,  10, "Geneva"; ;
	fontset = header, inactive, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = leftheader, inactive, L2,  12, "Times"; ;
	fontset = footer, inactive, noKeepOnOnePage, preserveAspect, center, M7,  12, "Times"; ;
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:[font = special1; inactive; preserveAspect; ]
                                              Colors in Mathematica

Mathematica  uses the RED-GREEN-BLUE system of describing colors.  A color is formulated by the procedure  

RGBColor[red, green, blue ]

with three parameters, each between zero and one (inclusive) and each specifying the amounts of one of the three basic colors -- red, green, and blue.  The color  RGBColor[1, 1, 1]  is white and the color  RGBColor[0, 0, 0]  is black.

The first cell below draws a single colored rectangle.  Notice how the rectangle's color is specified.  Evaluate the next cell.  Then try some experiments changing the rectangle's color.
;[s]
17:0,1;56,2;67,0;69,3;80,0;91,1;105,0;178,1;187,2;204,1;207,0;370,1;388,0;413,1;430,0;547,4;628,0;630,-1;
5:7,13,9,Times,0,12,0,0,0;6,13,9,Times,1,12,0,0,0;2,13,9,Times,3,12,0,0,0;1,13,9,Times,2,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
ColoredBox := {RGBColor[1, 0, 0], 
               Rectangle[{0, 0}, {1, 1}]}
               
Graf := Graphics[ColoredBox]
             
Show[Graphics[Graf],
     PlotRange -> {{0, 11}, {0, 11}},  
     AspectRatio -> Automatic,
     Axes -> True]
:[font = special1; inactive; preserveAspect; ]
The next cell generates a row of rectangles each with a different amount of red.  Notice the way in which the rectangles' colors are specified.  Evaluate the next cell and then experiment looking at shades of green and shades of blue.
;[s]
3:0,0;145,1;233,0;235,-1;
2:2,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
ColoredBoxes := Table[{RGBColor[x/10, 0, 0], 
                       Rectangle[{x, 0}, {x + 1, 1}]},
                       {x, 0, 10}]
               
Graf := Graphics[ColoredBoxes]
             
Show[Graphics[Graf],
     PlotRange -> {{0, 11}, {0, 11}},  
     AspectRatio -> Automatic,
     Axes -> True]
:[font = special1; inactive; preserveAspect; ]
The next cell generates a matrix of rectangles showing different combinations of red and green.  Evaluate it now and then experiment showing different combinations of red and blue, and of blue and green. 
;[s]
3:0,0;97,1;202,0;205,-1;
2:2,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
ColoredBoxes := Table[
                Table[{RGBColor[x/10, y/10, 0], 
                       Rectangle[{x, y}, {x + 1, y + 1}]},
                       {x, 0, 10}],
                       {y, 0, 10}]
               
Graf := Graphics[ColoredBoxes]
             
Show[Graphics[Graf],
     PlotRange -> {{0, 11}, {0, 11}},  
     AspectRatio -> Automatic,
     Axes -> True]
:[font = special1; inactive; preserveAspect; ]
The final cell generates a series of matrices like the red and green matrix above but adding increasing amounts of blue.  Evaluate it now. 
;[s]
3:0,0;122,1;137,0;140,-1;
2:2,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
Do[Show[Graphics[
           Table[
           Table[{RGBColor[x/10, y/10, z/10], 
                  Rectangle[{x, y}, {x + 1, y + 1}]},
                  {x, 0, 10}],
                  {y, 0, 10}]],
                  PlotRange -> {{0, 11}, {0, 11}},  
                  AspectRatio -> Automatic,
                  Axes -> True],
                  {z, 0, 10}]
^*)