Alexander Graham Bell in the context of Commemorative stamp

Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electrical or electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telephone, television, and radio.

Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Other early pioneers in electrical and electronic telecommunications include co-inventors of the telegraph Charles Wheatstone and Samuel Morse, numerous inventors and developers of the telephone including Antonio Meucci, Philipp Reis, Elisha Gray and Alexander Graham Bell, inventors of radio Edwin Armstrong and Lee de Forest, as well as inventors of television like Vladimir K. Zworykin, John Logie Baird and Philo Farnsworth.

Twisted pair cabling is a type of communications cable in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted balanced pair, a twisted pair reduces electromagnetic radiation from the pair and crosstalk between neighboring pairs and improves rejection of external electromagnetic interference. It was invented by Alexander Graham Bell.

For additional noise immunity, twisted-pair cabling may be shielded. Cable with shielding is known as shielded twisted pair (STP) and without as unshielded twisted pair (UTP).

A telephone, commonly shortened to phone, is a telecommunications device that enables two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from Ancient Greek: τῆλε, romanized: tēle, lit. 'far' and φωνή (phōnē, voice), together meaning distant voice.

In 1876, Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice at a second device. This instrument was further developed by many others, and became rapidly indispensable in business, government, and in households.

The invention of the telephone was the culmination of work done by more than one individual, and led to an array of lawsuits relating to the patent claims of several individuals and numerous companies. Notable people included in this were Antonio Meucci, Philipp Reis, Elisha Gray and Alexander Graham Bell.

Antonio Santi Giuseppe Meucci (/meɪˈuːtʃi/ may-OO-chee, Italian: [anˈtɔːnjo meˈuttʃi]; 13 April 1808 – 18 October 1889) was an Italian inventor and an associate of Giuseppe Garibaldi, a major political figure in the history of Italy. Meucci is best known for developing a voice-communication apparatus that several sources credit as the first telephone.

Meucci set up a form of voice-communication link in his Staten Island, New York, home that connected the second-floor bedroom to his laboratory. He submitted a patent caveat for his telephonic device to the U.S. Patent Office in 1871, but there was no mention of electromagnetic transmission of vocal sound in his caveat. In 1876, Alexander Graham Bell was granted a patent for the electromagnetic transmission of vocal sound by undulatory electric current. Despite the longstanding general crediting of Bell with the accomplishment, the Italian Ministry of Cultural Heritage and Activities supported celebrations of Meucci's 200th birthday in 2008 using the title "Inventore del telefono" (Inventor of the telephone). The U.S. House of Representatives in a resolution in 2002 also acknowledged Meucci's work in the invention of the telephone, although the U.S. Senate did not join the resolution and the interpretation of the resolution is disputed.

Elisha Gray (August 2, 1835 – January 21, 1901) was an American electrical engineer who co-founded the Western Electric Manufacturing Company. Gray is best known for his development of a telephone prototype in 1876 in Highland Park, Illinois. Some recent authors have argued that Gray should be considered the true inventor of the telephone because Alexander Graham Bell allegedly stole the idea of the liquid transmitter from him. Although Gray had been using liquid transmitters in his telephone experiments for more than two years previously, Bell's telephone patent was upheld in numerous court decisions.

Gray is also considered to be the father of the modern music synthesizer, and was granted over 70 patents for his inventions. He was one of the founders of Graybar, purchasing a controlling interest in the company shortly after its inception.

AT&T Inc., an abbreviation of its predecessor's former name, the American Telephone and Telegraph Company, is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's third largest telecommunications company by revenue and the third largest wireless carrier in the United States behind T-Mobile and Verizon. As of 2023, AT&T was ranked 32nd on the Fortune 500 rankings of the largest United States corporations, with revenues of $122.4 billion.

The modern company claims the history of the original AT&T founded in 1885 and all relevant history is found on the company's website. The company to bear the AT&T name began as a merger of the SBC Corporation (an original Baby Bell) and AT&T Corporation (Ma Bell). SBC began its history as the American District Telegraph Company, formed in St. Louis in 1878. After expanding services to Arkansas, Kansas, Oklahoma and Texas through a series of mergers, it became the Southwestern Bell Telephone Company in 1920. Southwestern Bell was a subsidiary of the original American Telephone & Telegraph Company, itself founded in 1885 as a subsidiary of the original Bell Telephone Company founded by Alexander Graham Bell in 1877. In 1899, AT&T became the parent company after the American Bell Telephone Company sold its assets to its subsidiary. During most of the 20th century, AT&T had a near monopoly on phone service in the United States through its Bell System of local operating companies. This led to AT&T's common nickname of "Ma Bell". The company was formally rebranded as AT&T Corporation in 1994.

The second millennium of the Anno Domini or Common Era was a millennium spanning the years 1001 to 2000. It began on January 1, 1001 (MI) and ended on December 31, 2000 (MM), (11th to 20th centuries; in astronomy: JD 2086667.5 – 2451909.5).

It encompassed the High and Late Middle Ages of the Old World, the Islamic Golden Age and the period of Renaissance, followed by the early modern period, characterized by the European wars of religion, the Age of Enlightenment, the Age of Discovery and the colonial period. Its final two centuries coincide with modern history, characterized by industrialization, the rise of nation states, the rapid development of science, widespread education, and universal health care and vaccinations in the developed world. The 20th century saw increasing globalization, most notably the two World Wars and the subsequent formation of the United Nations. 20th-century technology includes powered flight, television and semiconductor technology, including integrated circuits. The term "Great Divergence" was coined to refer the unprecedented cultural and political ascent of the Western world in the second half of the millennium, emerging by the 18th century as the most powerful and wealthy world civilization, having eclipsed Qing China, Edo Japan, the Islamic world and India. This allowed the colonization by European countries of much of the world during this millennium, including the Americas, Africa, Oceania, and South and Southeast Asia.

The Reis telephone was an early sound transmitting device, invented by Philipp Reis in 1857. Reis's first successful work is dated to October 1861. When properly set up, it would allow verbal communication via electronic signals. Many sources credit Reis as the inventor of the first telephone. Others point to the prior work of Antonio Meucci, or to later work of Elisha Gray or Alexander Graham Bell. However it is generally agreed that Reis coined the word telephon -- which has been Anglicised to telephone.

The Elisha Gray and Alexander Graham Bell controversy concerns the question of whether Elisha Gray and Alexander Graham Bell invented the telephone independently. This issue is narrower than the question of who deserves credit for inventing the telephone, for which there are several claimants.

At issue are roles of each inventor's lawyers, the filing of patent documents, and allegations of theft.

Alexander Melville Bell (1 March 1819 – 7 August 1905) was a teacher and researcher of physiological phonetics and was the author of numerous works on orthoepy and elocution.

Additionally he was also the creator of Visible Speech which was used to help the deaf learn to talk, and was the father of Alexander Graham Bell.

A laboratory notebook (colloq. lab notebook or lab book) is a primary record of research. Researchers use a lab notebook to document their hypotheses, experiments and initial analysis or interpretation of these experiments. The notebook serves as an organizational tool, a memory aid, and can also have a role in protecting any intellectual property that comes from the research.

Graham Bell Island (Russian: Остров Греэм-Белл, Ostrov Greem-Bell) is an island in the Franz Josef Archipelago in the Arctic Ocean, and is administratively part of Arkhangelsk Oblast, Russia.

The photophone is a telecommunications device that allows transmission of speech on a beam of light. It was invented jointly by Alexander Graham Bell and his assistant Charles Sumner Tainter on February 19, 1880, at Bell's laboratory at 1325 L Street NW in Washington, D.C. Both were later to become full associates in the Volta Laboratory Association, created and financed by Bell.

On June 3, 1880, Bell's assistant transmitted a wireless voice telephone message from the roof of the Franklin School to the window of Bell's laboratory, some 213 meters (about 700 ft.) away.