History

Until the advent of modern postal systems, most houses and buildings were not numbered. Streets may have been named for landmarks, such as a city gate or market, or for the professions of their inhabitants. In many cities in Asia, most minor streets were never named. This is still the case today in much of Japan. When postal systems were introduced, it became necessary to number buildings to aid in mail delivery.

Current addressing schemes

House numbering or naming

In most English-speaking countries the standard is an alternating numbering scheme progressing in one direction along a street, with odd numbers on one side (usually west or south) and even numbers on the other (usually north or east), although there is significant variation on this basic pattern. Cities in North America, particularly those planned on a grid plan, often incorporate block numbers, quadrants (explained below), and cardinal directions into their street numbers, so that in many such cities, addresses roughly follow a Cartesian coordinate system. Some other cities around the world have their own schemes.

Although house numbering is the principal identification scheme in many parts of the world, it is also common for houses in the United Kingdom and Ireland to be identified by name, rather than number, especially in small towns. In these cases, the street name will usually follow the house name. A fictional example of such an address might read: "Smith Cottage, Frog Lane, Barchester, Barsetshire, BA9 9BA" or "Dunroamin, Emo, Co. Laois, Ireland".

Quadrants