The idea for Ethernet was born fifty years ago in May 1973 when Robert Metcalf coined the word Ethernet. He had been studying ALOHAnet, developed at the University of Hawaii in 1971 and was the first public demonstration of a wireless packet data network. Metcalf used the work Ethernet as a reference to luminiferous aether, a concept postulated in the 17th century to explain how light could be transmitted through a vacuum.