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.

Yellow number plate

Commercial vehicles such as trucks and taxis have a yellow number plate with black text. These vehicles can be used for any commercial purposes. However, the driver of the vehicle must have a commercial driving permit.

Black number plate with yellow lettering

These are commercial vehicles available on rent for self-drive. These cars can be put to any commercial purpose without the limitation of the driver having to own a commercial driving permit.