10 codes

Tactical communications, like you hear on public safety radio, are all about being brief and to the point. In order to communicate quickly, codes and signals have been developed to allow personnel to get their point across using the minimum of words. There are numerous variations of 10 codes (abbreviations used by public safety officials to describe various conditions) used throughout the country. They can and do vary even from one county to the next.

Generically, these are referred to as brevity codes; the linked article serves as an index to lists of such codes.