A feature of NY streets is the green or red globe lamps indicating subway stations. Green means open and tells you it’s an entrance. Red lamps means exit only. The original system was created in the 1980s, when the token was still used as fare, and employed a traffic light colour scheme of green, yellow, and red. The different coloured globes were meant to convey to travellers whether a specific subway entrance was open 24hours with a token booth (green), open with a part-time token booth (yellow), or closed all the time with no booth (red). Yellow lamps were phased out leaving us with just the green and red you see today.