Why "Alpha?!"

The reason the transparency color option is called "Alpha" in Adobe Flash:

So you've sat through class; Adobe Flash Day 3. You're now making a slide show on your own. You've imported images, you've made them all symbols and now you're adding the fade in and fade out effects. You select your graphic symbol, cruise on down to the Properties tab and see "Color: None." Confidently, you select the drop-down menu to make your fade-out transition effects and see....Alpha? How does that even make sense?!

From what i can find, it all goes back to the development of a type of code made up of 0s and 1s that was created in the 70s. This code, which refers specifically to an element called the "alpha channel," is used for storing information about a 2D image in computer graphics. The 0s and 1s represent if there is any information to be saved per pixel. (A 0 indicates a fully transparent color and a 1 represents a fully opaque color.) I'm assuming they chose the word "Alpha" for this topmost channel because "alpha" is the first letter of the Greek alphabet (get it? ALPHAbet?) like the letter "A" (get it? A for ALPHA?!) Anyway - the process of Alpha compositing is adjusting the values in the alpha channel (the top layer where color information is stored on a per pixel basis) so as to combine the image with it's background to give it a transparent effect.

Get This!:
For the invention and development of the alpha channel, Smith, Catmull, Porter, and Duff won a technical Academy Award in 1996!!
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Sources:
1.http://en.wikipedia.org/wiki/Alpha_compositing
2.http://research.swtch.com/2008/01/alpha-compositing.html