XYZ direction pointers

[rpjd]

When you click on rotate for example, you see a yellow ball with XYZ pointing arrows appearing. When I click move (moving a part around an axis) and select a part, I get a blue ball with directional pointers on an edge of the part. Why is this? Now when I select a part, everything moves, not just the one part I selected, which should be the only part moving! Any ideas?

 

[rpjd]

In assembly, when rotating, a set of XYZ coordinates appears. Why when using the move command, does a second set of XYZ coorinates appear? This second set of coordinates nullifies and movement when rotating a part about an axis. Is there a way of preventing this second set of coordinates?