The invention of radiotelegraphy (wireless telegraphy) communication around 1900 allowed telegraph signals to be sent by radio. An operator at a radio transmitter would tap on a telegraph key, turning the transmitter on and off, sending pulses of radio waves through the air, and at the receiving station a radio receiver would receive the pulses and make them audible as a sequence of beeps in the earphone, and the receiving operator would translate the Morse code to text and write it down. High speed systems used paper tape to send and record the message. Guglielmo Marconi's demonstration of transatlantic radiotelegraphy transmission in 1901 showed that the wireless telegraph could be a useful long distance communication technology which didn't require the costly installation of a telegraph wire. Around 1906 industrial nations began building powerful transoceanic radiotelegraphy stations to communicate with other countries and their overseas colonies. By World War I these were integrated with landline telegraph networks, so citizens could go to a telegraph office and send a person-to-person telegraph message by radio to another country. This was written down on a standardized form called a "radiogram". International radiotelegraphy was expensive so radiograms were mostly used for business and commercial communication.