jwllorens:
I really appreciate your help, that clears up a lot of my questions.However, I am having a little trouble understanding what is going on in the diagram you linked.
The part that is confusing to me is the transistor and the diode. I don't understand why the diode is needed there, or why you would ever want current to flow back towards the 5v output on the arduino?
Also, I do not have a 4001 diode, but I have a 4007. Will the 4007 work in that diagram as well?
I also do not have that transistor, but I have this one: SM945 | PDF | Bipolar Junction Transistor | Electrical Circuits.
for the diode, have a read here : Flyback diode - Wikipedia
Can't say that I understand it fully myself, but have taken it as a serious requirement from other posts that the guru's have commented on.
As far as I understand, the main difference between the 4001 and the 4007 is that the 4001 can only manage a 35V reverse voltage, and the 4007 a 700V reverse voltage. I have used both in the past on relays.
As far as the transistor is concerned, sorry, but we'll have to wait for one of the guru's to look at that one.