On the lilypond-user mailing list, there was an issue on using the \absolute and \relative environments with octavation marks (' and ,) in lilypond. In a reply to the thread someone posted a small piece to remember which octavation mark corresponds to which note, so I thought I would post it here together with another note-chart I had made earlier so that I could actually find these from the web.

Octavation Marks

GHB scales and modes

The following images show the possible scales and modes for the Great Highland Bagpipe (GHB).

The idea is that you can see the actual scale between two bar lines, with the black notes playable by the GHB. This way, you can see how the range compares with the various scales.
Red notes in the images might are "off-key" for the GHB and are normally not reachable, however in some instances they might be cross-fingered.