The National Radio Institute-McGraw Hill Continuing Education Center was a private, postsecondary, for-profit correspondence school based in Washington, DC from 1914 to 2002. The school originally trained students to become radio operators and technicians. (In 1922, the term "radiotrician" was coined for NRI graduates and registered with the U.S. patent office in 1928). NRI conducted training courses via mailed lessons, a form of asynchronous learning. NRI's initial home-study course offerings were in radio (transmitter and receiver) repair, as well as radio telegraphy & telephony. These courses were designed to be comprehensive, covering all facets of radio technology, including radio operation, broadcasting, manufacturing, sales, and service. An F.C.C. license exam preparation course was