I'm getting this from the "Getting Started with Ardunio" Book by makershed.
This diagram is throwing me off, and I'm hoping you guys can clear it up. http://imgur.com/oRFZT
1) Why are we using a resistor for the switch?
2) If we Need the resistor, does it matter where the resistor is placed in the circuit? Shouldn't it be on the 5V side, before the switch?
3) Does the wire with the red arrow benefit from the resistor?
4) Shouldn't we be using a resistor for the LED?