In the United States, at least, house numbers have nothing to do with the Postal Service, but are assigned by city planning commissions and the like. How they do it, however, varies extremely.
In Manhattan, for example, where I live, streets run both east and west from the central spine, and are numbered starting at the spine and working outward. However, even numbers are always on the south side of a street. Manhattan avenues are numbered northwards; for details, see the Comments.
In Queens to find locations best —
Avenues, roads and drives run west;
But ways to north and south, 'tis plain
Are street or place or even lane;
While even numbers you will meet
Upon the west and south of street.
(You can sing it to the tune of "Little Brown Jug".)
What about the "100 house numbers per block" convention? This does not hold in the older parts of older U.S. cities (Manhattan does not obey it south of 8th St. or so), but is quite general in the U.S. as a whole.
In rural parts, it is not uncommon for houses to be neither named nor numbered; my house in the country has no "address" at all, and only post office boxes are provided (no mail delivery). Anyone who wants to reach me by snail (extremely snail) mail, can do so at: