Christmas lights are a big part of the holiday season. As November and December roll around, you might see strands of lights everywhere -- on Christmas trees, houses, shrubs, bushes and even the occasional car! Have you ever wondered how these lights work? Why is it that if you pull out or break one of the bulbs, the whole strand of lights goes out? And how do they create the lights that sequence in different color patterns?

In this edition of HowStuffWorks, we'll look at Christmas lights so you can understand everything about them!