Anything that will allow electricity to pass through it is a conductor. Metals are typically good conductors with copper being one of the best.
If the ends of the wires are too far apart, the nut won’t go on properly. Be sure the ends match up before twisting them together. If necessary, snip off a bit at the tip to get them even before attaching the connector.
Decide on the location for the new electrical fixture and where the source will be. Determine inside of which walls and ceilings the cable must be run. For example, with a new ceiling fixture using a source from an existing wall receptacle, the cable will have to be run inside the wall cavity, through the top plate, into the ceiling cavity, and on to the new fixture.
A device for controlled interruption of current flow in a circuit. A single-pole, single-throw (SPST) light switch is the most common type found in household circuits. These have one set of contacts and can be either ON or OFF. A single-pole, double-throw (SPDT) switch has two sets of contacts and can alternate between them to divert current between two separate paths. A 3-way switch is an example of a SPDT household switch.