What wires go together on a ceiling light?

A black wire, green wire, and white wire are the ones you need to be familiar with. While working on your project, you will notice that these three wires are joined together with the use of twist-on wire connectors. Its better to work on these wires with hands that are free of anything else – like a ceiling fixture.

Does it matter which way you wire a light bulb?

True, the lamp will usually work either way. Remember when repairing lamps, the neutral wire in the lamp cord is marked (usually with a rib or ribs) and it connects to the wide blade of the plug at one end and to the neutral screw (usually silver but may have some other identification) at the other end.