They are wired. Or at least almost always so.
It is possible to have them operate in other ways. Originally, they were candles hung in the trees - not suggested. (Wow, what an idea! See a psychiatrist before you try this!) I suppose it would be possible to have LED lights with tiny batteries for special purposes.
Generally in a parallel circuit
They are or were wired in series, one goes, they all go.
Usually, strings of Christmas lights light up a Christmas Tree. Nowadays, the lights are more likely to be LEDs.
Christmas lights
pops lights Rockefeller Christmas tree
No it will not. Evergreen trees (Christmas trees) are wrapped in Christmas lights spread throughout the world.
Christmas light hangers are used to secure Christmas lights to the Christmas tree. The hangers keep the lights from falling or sagging around the tree.
Always parallel. Homes should never be wired in series. (That would be like the old Christmas tree lights where, if one bulb burned out, the entire string would not light up.)
when lights are wired in series same amount of current flows through each light through out wire so the intensity of lights dont decrease and all lights glow with same intensity
300 lights
1000-3000 lights
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