The light bulbs used in the manufacture of holiday lights are made at a circular table. The table rotates, and, as it turns, each glass module is processed into a completed bulb. First, the module is heated, then it is blown into the bulb shape.he light bulbs used in the manufacture of holiday lights are made at a circular table. The table rotates, and, as it turns, each glass module is processed into a completed bulb. First, the module is heated, then it is blown into the bulb shape.