or transit signal
is a name for various techniques to speed up
bus public transport
intersections with traffic signals. Buses normally signal their
impending arrival (for example via radio systems) and on their
arrival at the intersection receive green lights. This is often
combined with separate bus lanes
possibly this may only apply at the intersections themselves.
Bus traffic signals generally show a letter "B" to distinguish them
from ordinary traffic signals
Sometimes the green "B" is actually a white "B".
Trams and Light Rail
Trams and Light Rail Vehicles can also be given priority, in which
case the traffic signals show a letter "T".
Bus Priority in Calgary, Canada
Calgary, a blue signal typically above the pedestrian
signal will come on until the traffic light reverts to its normal