United States National Grid – Wikipedia

The United States National Grid (USNG) is a multi-purpose location system of grid references used in the United States.It provides a nationally consistent “language of location”, optimized for local applications, in a compact, user friendly format. It is similar in design to the national grid reference systems used in other countries. The USNG was adopted as a national standard by the Federal …

https://en.wikipedia.org/wiki/US_National_Grid