An APB, or all-points bulletin, is an electronic information broadcast sent from one sender to a group of recipients to rapidly communicate an important message. It is primarily used in the field of policing and is an alert sent to all police officers in an area, state, or country, with instructions to arrest a particular suspect or to be on the lookout for a particular vehicle or item of interest. APBs are sent through various types of media, including computer, radio, and paper. In the field of policing, an APB contains an important message about a suspect or item of interest, which officers may be in search of. They are primarily used for individuals who are classified as dangerous and for crimes of high priority. In these fields, the APB may also be known as a BOLO, for "be on (the) look-out".