Welcome lamp is a kind of automobile lighting, which is mainly installed at the bottom of the door and under the rearview mirror. Every time the driver and passengers open the door and get on the bus in advance, the light at the bottom of the door will flash and drive straight to the road. As soon as the door closes, it goes out, just like you open the door and get off. It is precisely because of its working mode that many riders call it the welcome light, which is also a relatively easy-to-understand name.