An Internet police scanner is a live feed of police-based information as it happens. These Internet scanners transmit fire and radio calls.
Traditionally, police scanners were similar to radios, and people using them would tune them to specific stations used by the police or fire department. When the police receive a call, it transmits over the scanner. Critics believe that when the public can access this information, it puts people in danger as it can alert criminals. Other people, however, believe the public should have access to the information. There are many mobile apps or other programs available to pick up these calls.