its becuase you ahve local selected in where i have made the red box
change it to view
basicly wat these option do is change the direction, insted of using the worlds X, Y, Z axis, it use the "local" ones to the selected verts, faces etc.
the other option in there do
screen, makes the axis more to where you ahve your screen so if you in left the axis will change to move on those axis, it also works with perspective, but i would not recomed you use it in there.
world, is the world axis, bacily if you have the grid up thats the axis
parent, works when you have linked object where childen objects get there pivot points from the parent.
never worked out wat gimbal did
and grid uses the grid axis, like world.
i think those are the meanings for them, but check the max help files, i could be worng.