Hello, I'm starting a small home improvement project that includes some electrical wiring. I have little electrical experience but from what I hear, it doesn't seem unfeasible for me to complete. My questions are: Do they sell a "two headed" electrical wire that I can splice into an existing line running through my wall? In terms of amp rating, how heavy duty do I need to go for a household electrical outlet? Can someone refresh my memory on what the colors of the wires (black, white, green, I think?) stand for?