Alpha blending is a convex combination of two colors allowing for transparency effects in computer graphics. The value of alpha in the color code ranges from 0.0 to 1.0, where 0.0 represents a fully transparent color, and 1.0 represents a fully opaque color.

The value of the resulting color when color Value1 with an alpha value of Alpha is drawn over a background of color Value0 is given by:

Value = Value0(1.0 - Alpha) + Value1(Alpha)
The alpha component may be used to blend to red, green and blue components equally, as in 32-bit RGBA, or, alternatively, there may be three alpha values specified corresponding to each of the primary colors for spectral color filtering.

Alpha blending is natively supported by these operating systems/GUIs:

1) Mac OS X
2) Windows 2000, XP
3) Most Linux graphical user interfaces (GUIs)

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