A 
pedestrian crossing is a designated point on a 
road at which some means are employed to assist 
pedestrians wishing to cross the road. Pedestrian crossings may have regular 
traffic lights (where those for the pedestrians are usually without yellow) or special coloured 
lamps to alert drivers of vehicles.
Pedestrian crossings are often at road crossings but also at other locations on busy roads with a good deal of fast moving traffic that would otherwise be perilous to attempt to cross, and near schools or in other areas where there are a large number of children.
In the USA, they are marked using the abbreviation Ped Xing.
See http://www.roads.dft.gov.uk/roadsafety/goodpractice/20.htm
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