Wireless telegraphy in the context of "Spark-gap transmitter"

Wireless communication (or just wireless, when the context allows) is the transfer of information (telecommunication) between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most common wireless technologies use radio waves. With radio waves, intended distances can be short, such as a few meters for Bluetooth, or as far as millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Somewhat less common methods of achieving wireless communications involve other electromagnetic phenomena, such as light and magnetic or electric fields, or the use of sound.

The term wireless has been used twice in communications history, with slightly different meanings. It was initially used from about 1890 for the first radio transmitting and receiving technology, as in wireless telegraphy, until the new word radio replaced it around 1920. Radio sets in the UK and the English-speaking world that were not portable continued to be referred to as wireless sets into the 1960s. The term wireless was revived in the 1980s and 1990s mainly to distinguish digital devices that communicate without wires, such as the examples listed in the previous paragraph, from those that require wires or cables. This became its primary usage in the 2000s, due to the advent of technologies such as mobile broadband, Wi-Fi, and Bluetooth.

Guglielmo Giovanni Maria Marconi, 1st Marquess (/mɑːrˈkoʊni/ mar-KOH-nee; Italian: [ɡuʎˈʎɛlmo marˈkoːni]; 25 April 1874 – 20 July 1937), was an Italian radio-frequency engineer, inventor, and politician known for his creation of a practical radio wave-based wireless telegraph system. This led to him being largely credited as the inventor of radio and sharing the 1909 Nobel Prize in Physics with Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy."His work laid the foundation for the development of radio, television, and all modern wireless communication systems.

As an entrepreneur and a businessman, Marconi founded the Marconi Company in the United Kingdom in 1897. In 1929, he was ennobled as a marquess (Italian: marchese) by Victor Emmanuel III. In 1931, he set up Vatican Radio for Pope Pius XI.

A telegraph key, clacker, tapper or morse key is a specialized electrical switch used by a trained operator to transmit text messages in Morse code in a telegraphy system. Keys are used in all forms of electrical telegraph systems, including landline (also called wire) telegraphy and radio (also called wireless) telegraphy. An operator uses the telegraph key to send electrical pulses (or in the case of modern CW, unmodulated radio waves) of two different lengths: short pulses, called dots or dits, and longer pulses, called dashes or dahs. These pulses encode the letters and other characters that spell out the message.

A Tesla coil is an electrical resonant transformer device designed by inventor Nikola Tesla in 1891. It is used to produce high voltage, low current, high frequency alternating current. Tesla experimented with a number of different configurations consisting of two, or sometimes three, coupled resonant electric circuits.

Tesla used these devices to conduct innovative experiments in electrical lighting, phosphorescence, X-ray generation, high-frequency alternating current phenomena, electrotherapy, and the wireless transmission of electrical energy. Tesla coil circuits were used commercially in spark-gap transmitters for wireless telegraphy until the 1920s, and in medical equipment such as electrotherapy and violet ray devices. Today, their main usage is for entertainment and educational displays, although small coils are still used as leak detectors for high-vacuum systems.

A telegraphist (British English), telegrapher (American English), or telegraph operator is a person who uses a telegraph key to send and receive Morse code messages in a telegraphy system. These messages, also called telegrams, can be transmitted electronically by land lines, or wirelessly by radio.

The siege of Toma was a bloodless action during the First World War on the island of New Pomerania (now New Britain) between 14 and 17 September 1914 as part of the occupation of German New Guinea by the Australian Naval and Military Expeditionary Force (AN&MEF). Australian forces had been dispatched to seize and destroy German wireless stations in the south-west Pacific because they were used by the German East Asian Cruiser Squadron of Vice Admiral Maximilian von Spee which threatened merchant shipping in the region. New Zealand provided a similar force for the occupation of German Samoa. Ultimately the German colonial government was forced to surrender after being surrounded, ending the last significant resistance in the territory.