If you are wondering about your home electrical unit, consider learning about electrical wiring and how you can manage this at your house. There are some terms that you should become familiar with, including line/ hot, load, neutral, and ground. You may be working with a switch or outlet, and you will want to remove the cover plate first in order to remove the switch and expose the wires.
The cables in the back of the box each have a job, and you can locate each of these by following some steps by experienced people.
The power cable is the hot cable and is the most important because it carries all the power. The load, or red wire, is the device that is getting powered by the hot cable. This will go to a lightbulb, fan, or other appliance for electrical use. The neutral wire is the second part of the cable that returns any volts not used back to the system. The ground wire is typically copper or green and protects the circuit from surges of electricity coming from the source.