Hi there, I'm new here. I'm working on a project and I have a technical question regarding the wiring of the components. First, is wall power AC or DC? It seems that if there is a positive and negative terminal in the wall outlet, it would be DC (like a battery). But then again my understanding is that all electric power has to flow from opposite charged terminals. This project will use 120v wall outlet power wired in parallel to a heating element and and a 12v fan. The heating element will use 120v power but the fan, being rated at 12v, needs to transform that 120v to 12v. I've been searching for step down transformers but it seems that only high voltage transformers can be found. This makes me believe that a 'step down transformer' exists in the electronics industry, its just not referred to as such. I was just wondering, what type of device should be used in series with the 12v fan to transform the 120v power so it doesn't destroy the fan? I've opened up a few voltage transforming electronic devices around the house and taken a look at the components but I don't know what the devices are called so I can't begin ordering them from electronics suppliers. Any help would be appreciated.