You might have observed it while travelling, but do you know why certain types of vehicles follow a similar colour-text code for the number plate and the others follow a different one? There are various parameters that decide which vehicle bears which coloured number plate. White number plate Cars bearing black lettering on a white background are private vehicles. These are used solely for private purposes and can't be used for any commercial purpose.

Light blue number plate

Vehicles belonging to foreign consulates bear white lettering on a light blue background. These number plates bear UN, CD or CC, which stand for United Nations, Diplomatic Corps and Consular Corps respectively.

The number following UN, CD or CC refers to the country (as given in the list below)