A ZIP code is a postal code used within the United States to help the United States Postal Service (USPS) route mail more efficiently. It is a 5-digit number that specifies an individual destination post office or mail delivery area. The first three digits of a ZIP code usually indicate the central mail processing facility, also referred to as a sec center or sectional center facility to which that ZIP Code belongs. The basic 5-digit format was first introduced in 1963 and later extended to add an additional 4 digits after a dash to form a ZIP+4 code. The additional 4 digits help USPS more precisely group mail for delivery.

To find a specific ZIP code, you can use the ZIP Code™ Lookup tool on the USPS website. You can enter a corporate or residential street address, city, and state to see a specific ZIP Code™, or enter a city and state to see all the ZIP Codes™ for that city. You can also find ZIP codes by address, city, or state on the United States Zip Codes website. Additionally, there are other websites like What is my Zip Code and Map Developers that can help you find your ZIP code based on your location.