DMR stands for Digital Mobile Radio, which is a digital radio communication standard used by various industries and organizations. It provides clear and reliable voice communication and some limited data transmission capabilities. DMR is designed to be more efficient and secure than traditional analog radio systems, and it offers advanced features such as GPS tracking, text messaging, and data transmission. DMR radios are available in different tiers, with Tier II providing conventional radio systems for smaller organizations or networks, and Tier III providing trunked radio systems for larger organizations or networks with more advanced features and capabilities.