A Postal code is a series of numbers or letters and numbers used by a post office to help identify where a letter or parcel should be sent.The code can be read by machines, this speeds up sorting mail.
In the United Kingdom the first part of the post code has one or two letters and one or two numbers. This identifies the post town and an area in the post town. The second part is used to identify an even smaller area, down to just one street or a few house in a long street.