Emergency response systems are software platforms that coordinate first responders during emergencies. They consist of three core components: 911 call-taking systems (capture location and call details), CAD (Computer Aided Dispatch, assigns units), and AVL (Automatic Vehicle Location, tracks responder positions on a map). When someone dials 911, the system captures their location (via cell tower triangulation or address), alerts the dispatcher via CAD, suggests nearest available units, and monitors their position via AVL as they respond. All of this must happen in seconds, with 99.99% reliability.