The outdoor carriage lights were first used in seventeenth century. At that time it was installed on both side of the carriage. Coachman used to see the road at night by these lights, because at that time the carriage wheels were made of wood, so if coachman could not see the road properly at night and the wheel stuck in any large stone or obstacle, there was every chance of breaking the wheels. So it was very much necessary for the coachman to see the proper path at time of driving the carriage. On the other way, it helped people on the road also, because from these lights they got to know that a carriage is coming. So at that time it was used only for safety purpose of both the passenger of the carriage and the people on the roads.
But nowadays the concept of using outdoor carriage lights has been thoroughly changed. That time these were mounted on the side of the carriages, but now they have become fashionable outdoor lighting lamps. It changed its place of installation from the side of the carriages to the driveway or the patio of your house.
The authentic carriage lights were made from wood but now it is mainly made from nickel or chrome or glass. The light inside has also been changed from candle to modern day solar light or LED light. The only thing that has not been changed is the look and feel of the lamp .That is why they still call it as outdoor carriage lights. They carry the original history of themselves with their name. May be this is one of the reasons that it is well accepted as a classy outdoor lighting lamps and people love to use it as a porch light or walkway light.