what does color alpha do?

[drEDN4wt]

when you create a colour with

Color.new( r, g, b [ , a])
what does the alpha setting do?

[cloud_952]

In most things, it has to do with transparency (how transparent/opaque) an object is. At least that's how it works in other things that I'm aware of. Can also be used for selecting which color is invisible in an image.

[my psprecious]

thanx guys been wondering how to do that for 2 days