I'm working on project 9 of the starter kit - the motorized pinwheel.
Here is the schematic:
(if img not showing: https://goo.gl/tqZmKD)
My question is, why is the 10k resistor needed after the switch? Why can't it just go straight to ground? The switch's output just connects to a digital pin, it doesn't care how much voltage there is, correct?