Question

When one light in a string of holiday lights goes out and the rest of the string also goes out, what type of circuit is used?

Answer 1

I would assume all the lights are wired in series because if they were in parallel the electricity would skip the burnt out light and light all the lights ahead of it. If you look at the wiring in a string of lights this type too there are only two wires running through the string. If it was in series, each light would have a set of wires.