A postcode is a unique identification number for a place, usually a city, and is assigned by the US Postal Service based on the area code. In some cases, a postal code can be assigned to an individual land lot. In Brazil, for example, large receivers receive the suffix 900-959. In this case, the number is associated with a particular place and is a part of the local area code.
The suffix is used in a variety of ways, and is often related to a town's land lot and any points of access to that lot. In most English-speaking countries, the postcode comes last, following the name of the city. It may follow the city on the same line or a new one, and in some countries, it is written at the beginning of the address. However, in the Czech Republic, Belarus, Kyrgyzstan, and Russia, the postal code comes first.
Postcodes have two parts: an outward portion that identifies a postal district, and an inward part that refers to a specific part of a town. The outward part of a postcode is a number indicating a postal district, which is the area in which the delivery office is located. A single outward number can also be used for multiple post towns, and there are even times where a single postal district lies within several different post towns.