Usps.zip -

Indicate regional areas or a Sectional Center Facility (SCF) , which acts as a central sorting hub.

Introduced on , the ZIP ( Zone Improvement Plan ) code was designed to modernize mail delivery by enabling automated sorting. Before its adoption, mail passed through 17 sorting steps; the code reduced this significantly by providing a geographic "map" within a few digits. The 5-Digit Core: USPS.zip

Represents a broad geographic area of the country (e.g., "0" for the Northeast, "9" for the West Coast). Indicate regional areas or a Sectional Center Facility

Pinpoint specific post offices or delivery zones within that region. mail passed through 17 sorting steps