What's the difference between the color of a car's license plate, like yellow, green, blue, and especially black. Military and police cars this I understand

The license plate*** has four colors, yellow, blue, white and black.

Yellow: large buses, trucks or operating vehicles, such as: buses, trucks, black characters on a yellow background, in addition, for container trucks, there is "Shanghai A ***** hanging" style, more than a "hanging" word, for coaching vehicles, driving school, there is "Shanghai A ***** hanging" style, more than a "hanging" word, for coaching vehicles, driving school, there is "Shanghai A ***** hanging" style, more than a "hanging" word. For the driving school, there is the style of "Shanghai A ***** school".

Blue: small buses, private cars or operating vehicles, for example: cabs and private cars are basically blue license plate, white letters on a blue background, the same format as the yellow license plate.

White: license plates used by police and armed police, troops.

Police: black letters on a white background, in which the word "police" is red, there is no restriction on the scope of access, can go anywhere.

Armed police: format: WJ (08)-*****, black letters on a white background, in which "WJ" is the meaning of the armed police, "(08)" on behalf of the Shanghai armed police force number, "*" number is full of numbers. The "*" sign is full of numbers. There is another, WJ (08)-***** eliminate, "eliminate" the word red, is the firefighters open fire truck.

Black: consulate license plate, white letters on a black background, the format is: Shanghai A ***** collar, less, is the exclusive use of consulates