STANAG

In NATO a Standardization Agreement (STANAG) defines processes, procedures, terms, and conditions for common military or technical procedures or equipment between the member countries of the alliance. Each NATO state ratifies a STANAG and implements it within their own military. The purpose is to provide common operational and administrative procedures and logistics, so one member nation's military may use the stores and support of another member's military. STANAGs also form the basis for technical interoperability between a wide variety of communication and information systems (CIS) essential for NATO and Allied operations.

STANAGs are published in English and French, the two official languages of NATO, by the NATO Standardization Office in Brussels.

Among the hundreds of standardization agreements (current total is just short of 1300) are those for calibres of small arms ammunition, map markings, communications procedures, and classification of bridges.

...
Wikipedia