What is pink noise?


What is pink noise? I want to know about pink noise. I make a request.
bluesky
Alcides - your pink/white noise analysis is correct, but you're off by an octave on the piano's low end. The standard 88-key piano goes down to ~28Hz, also the 440Hz A is above middle C, not below.
So if you were going to measure in-room frequency response, would you use white noise or pink noise?
And how do you measure sound at any particular frequency? Rat Shack SPL meter and Stereophile test tones miss a large part of the frequency spectrum. I would think using white or pink noise would be much more accurate - IF it can be done.