In case of emergency (ICE) is a system that was conceived in the mid 2000s that enables those at accident scenes - paramedics, firefighters, and police as well as hospital personnel, to contact next of kin to obtain important medical or support information.
Unfortunately these days for security purposes, many mobile phone owners now lock their mobiles, requiring a pin number to access the device. In response to this problem, many device manufacturers have provided a system to show some text while the mobile is 'locked'. The owner of the phone can specify their "In Case of Emergency" contact and also a "Lost and Found" contact.
Please speak to your service providers for more information but whatever you do, put an ICE number into your phone now!