How Common Items Became the Iconic Colors They Are
Tom BlankofWeird History explains how certain common items took on specific hues that have lived on. Usually, the reason for the item's iconic color came by accident or by what type of ingredients happened to be lying around at the time.
Of course a pencil is yellow! Well, yes, a candy cane should be red and white. But these things didn't always have these telltale colors. Some were changed - to be easier marketed, or for safety reasons. Sometimes the iconic color was an accident during the creation process, or simply the easiest thing people had on hand.
These items include the flag of surrender (white because of its universal availability), bubble gum (pink because that was the only food dye available), barns (red due to iron oxide), traffic lights (red, yellow, and green which were adapted from train lights), tennis balls (fluorescent yellow/chartreuse due to the advent of color TV), pencils (yellow because it was unique at the time and the colors of the Austro-Hungarian flag), dollar bills (green due discourage forgery), jeans (blue due to softening agents), and doctor's uniforms (white to symbolize spotlessness).