Digital Mobile Radio (DMR) is an open digital radio standard developed by the European Telecommunications Standards Institute (ETSI). It is widely used in commercial, amateur, and public safety radio communications. DMR uses TDMA technology, allowing two voice or data channels to share a single 12.5 kHz frequency, improving spectrum efficiency. The standard supports clear digital voice, text messaging, GPS location, and data services. DMR radios are organized into tiers, including Tier I (license-free), Tier II (licensed conventional), and Tier III (trunked systems). DMR is popular for its reliability, interoperability, and cost-effective digital communication.