Raspberry pi inside keyboard

[nebo]

I have a raspberry pi just sitting around and I came across this project that someone did with theirs. Well as it so happens I also have the same keyboard that is also not in any real use so I figured what the hell. Looking through it all it seems simple enough but I have a few questions about the electrical side of things that I don't understand as well (and I couldn't get a hold of the author or he is out somewhere). Why the need for resistors? Everything looks like it is just soldered directly to where it would fit anyways besides the power but that is just rerouted.

Thanks for any help. If there is some basics to read up on for this kind of thing that'd be great, google didn't help much.

[fohat.digs]

I think that Ezrahilyer did a Raspberry Pi all-in-one, contact him.

[nebo]

Thanks, I'll hit them up. I think the only thing he used a resistor for was the single led on the back. Seems like a waste, I'll probably just route the audio to there to save time.