On sheet music, what does it mean when there are...?

Question

two flats together next to a single note. For instance, if there's a 'b' note that has to flats next to it, what does that mean? :)

Thank you so much. I learned to play classical piano by ear and am teaching myself to sightread music. I was stuck until now, thanks to you guys. :)

Answer 1

Double flat. Instead of moving down 1/2 step, you move down a whole step. E double flat would be D, and so on. The next question, of course, is why write it that way, instead of just writing the note for "D"? It has to do with rules of composition, intervals, keys, etc. Too complicated to get into here. But if you'd like to learn more about it, you can start with this:

http://library.thinkquest.org/15413/theory/theory.htm

Answer 2

That would be a "double flat". The pitch is a whole tone lower

Answer 3

It's called a double flat.
It means the pitch is a whole tone lower than the note.
So a Dbb will be a C.

Answer 4

Double flat indeed.