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The metro system in a large city must move millions of people every day without confusion. To do this, designers rely on a clear map and a simple set of colors. Each line is given its own color, so a passenger can follow a single shade from one station to the next. Signs at every platform repeat these colors and list the stops in order. Because the design is consistent, even a visitor who speaks no local language can usually find the right train.

A city's metro must carry millions of riders daily without —confusionconclusionconstruction. Designers achieve this with a clear map and simple colors, giving each line its own —colorcollarcaller so passengers can follow it from station to station. Signs repeat the colors and list the stops in —orderangerhonor, so even a visitor who speaks no local language can find the right train.