You may have the most powerful passport in the world, which is the passport that is held by residents of Japan, or the most rarest passport in the world. But the chances are pretty high that your passport either has a green, red, black, or blue passport.

As a matter of fact, there are no official rules on passports that prohibit countries from choosing certain colors or a set of design rules that they have to follow.

There are a few rules that imply on passports though, the ICAO (International Civil Aviation Organization) works to define the principles of air travel, and they suggest that countries all over the world should use specific type size, font for passports, and a certain typeface.

There are a number of compulsory aspects of these international identification documents.

Passports are also required to be made out of a material that allows them to bend in order to prevent creases. Passports are also needed to be made in a way that they can be read by a machine at a temperature of 14 degrees to 122 degrees Fahrenheit.

Also, passports should also be capable of holding air humidity that is up to 95 percent.

But even after all these recommendations set by the International Civil Aviation Organization, there is no official law that states your passport can’t be pink, violet, or a rainbow color passport.

Countries all over the world don’t just select a random color though, most countries prefer to use a simple dark color such as red, green, blue, and black.

According to experts, countries choose dark colors because they are more official and they can also hide dirt.

But there is a meaning behind each color.

Most Islamic countries go with green passports, this is because the green color is very significant in the Islam religion.