If you become injured and unconscious, first responders will immediately check your driver's license to ID you and contact your family.
Not everyone has family, but if you do, they may be at work or shopping. To reach them immediately ICE, cut a piece of plain card stock from your mail or your file folder . Make it about 2 inches wide and 3/4 of an inch high. Neatly print ICE, the name you want contacted, relationship, and CELL PHONE NUMBER. Scotch tape it to the top back of your driver's license, top only, so it can be flipped up to see back side of your license clearly. NOW you are covered.