Maybe you have the most powerful passport in the world, or perhaps you carry the rarest. No matter the case, your passport will likely be one of four colors: blue, green, red, or black. What gives? While there are no official rules regarding passport colors, countries do follow a certain set of norms when designing them. The International Civil Aviation Organization (ICAO), which works to define the principles of air travel, suggests that countries use a specific typeface, type size, and font for official documents like passports.
