1834 Carl F.Gauss and Ernst H. Weber build the electromagnetic telegraph. The telegraph was the first step to making electrical signals travel from one device to another.
1844 Samuel F.B. Morse demonstrates the Baltimore, MD, and Washington, DC, telegraph line.
1860 Philipp Reis develops a “telephon.” Reis's phone was the first instrument to transmit the spoken word.
1864 James C. Maxwell predicts electromagnetic radiation.
1866 The second transatlantic cable is installed. (The first failed after 26 days in 1858.) Telephone communication was available between the two countries.
1874 Alexander Graham Bell discovers the principle of the telephone.
1876 US Patent No. 174,465, issued on March 3 for “Improvements in Telegraphy.” Elisha Gray applies for a similar patent hours after Bell. Gray and Bell would fight for years in court as to who's telephone was "legal".
1877 Thomas Edison receives a patent in Britain for the “electro-motograph.” His carbon-based transmitter is still used in telephones today. First permanent outdoor telephone wire strung. Commercial telephone service begins in the United States.
1878 The workable exchange comes on line. It enables calls to be switched among any number of subscribers rather than requiring direct lines.
1879 Telephone subscribers began to be designated by numbers rather than names. This allows more subscribers per switching station.
1880s Long distance service was established and grew using metallic circuits.
1883 Thomas A. Edison discovers flow of electronics in a vacuum, called the "Edison effect," the foundation of the electronic tube.
1888 The common battery system, developed by Hammond V. Hayes, permitted a central battery to supply all telephones on an exchange.
1891 The first automatic dial system was patented by a Kansas City undertaker. Switchboard operators were no longer necessary to make a telephone call.
1894 Oliver Lodge demonstrates wireless communication over a distance of 150 yards. This is the beginnings of cell phone technology.
1900 The first coin telephone was installed in Hartford, Connecticut.
1906 Dr. Lee De Forest, began work on applying what was known as an “audion,” a three element vacuum tube, which could amplify radio waves, to telephony.
1911 American Telephone and Telegraph (AT&T) took control of Western Union Telegraph Company. This is the beginning of "Ma Bell" which would be the largest telephone company in the US until the 1980's.
1913 The Bell System bought the rights to De Forest’s patents, which were used for long distance telephone service. First long-distance wire link was on the New York to San Francisco circuit using loading coils and repeaters.
1915 Bell System completes a U.S. transcontinental telephone line. Everyone in the US was connected to each other.
1918 Ten million Bell System telephones were in service. Edwin H. Armstrong invents the superheterodyne receiver circuit. Calls became clearer and faster.
1921 Automatic switching of large numbers of calls was made possible using “phantom circuits,” which allowed three telephone conversations to be conducted on two pairs of wires. More people could use the same circuit so telephone companies did not have to build more switching stations.
1927 The “French” phone, with the transmitter and receiver in a single handset, developed by the Bell System was released on a widespread basis. Harold Black develops the negative-feedback amplifier at Bell Laboratories. This made the telephone signal less distorted.
1927 Transatlantic service from New York to London became operational, transmitted by radio waves. Underwater cables were no longer necessary.
1931 Teletypewritter service is initated. This machine sends printed type, like a typewriter, across telephone lines to be printed out on the other end. This is the beginnings of facsimile machines and also lets the deaf use the telephone.
1936 Research on electronic telephone exchanges began in Bell Labs and was ultimately perfected in the 1960s with AT&T’s Electronic Switching System (ESS).
1946 First commercial mobile telephone service put into service in 1946, linking moving vehicles to the telephone network by radio.
1946 Transmission via coaxial cables was accomplished. This wire has a center wire and insulation all around and reduces radio wave interference.
1947 Microwave radio transmission was used for long-distance telephony. The transistor, a key to modern electronics, was invented at Bell Labs by a team consisting of William Schockley, Walter Brattain, and John Bardeen.
1950s Microwave telephone and communication links are further developed.
1950 Time-division multiplexing is applied to telephony. People were now charged by the minute for their telephone calls.
1953 The laying of transatlantic telephone cables began. Calls could be made to European countries.
1958 All Number Calling (ANC) instituted to handle consumer demands for individual telephone numbers. A possible 9,999,999 numbers available.
1960s Videophones became more affordable and practical. People could now see who they were talking to.
1962 Telstar, the world’s first international communications satellite, was rocketed into orbit on July 10 with the collaboration between NASA and the Bell System. Telephone calls could now be "bounced" off a satellite to a switching station.
1963 Bell System introduces the touch tone phone. This telephone made a different beep for each number instead of counted clicks for each number.
1964 The electronic telephone switching system is placed into service. Calls are switched faster than before.
1965 The first commercial communications satilite, Early bird, is placed into service.
1966 K.C. Kao and G.A. Hockham publish the principles of fiber optic communications. This cable uses glass to send a light beam that carries thousands of calls.
1971 Intel Corporation develops the first single chip microprocesser, the 4004. The microprocessor would make telephones and switching systems smaller, lighter and faster to use.
1972 Motorola demonstrates the cellular telephone to the FCC. People could call each other without wires.
1980 Bell System FT3 fiber optic communication is developed.
1981 IBM PC is introduced. The Internet would use the telephone lines in the future to transmit information through a personal computer.
1982 AT&T agrees to breakup its Bell System telephone companies. "Ma Bell" becomes a bunch of "Baby Bells".
1985 FAX machines become popular. A printed sheet of paper can be sent across telephone lines and received whole on the other end.
1989 "Pocket" cellular telephone is introduced by Motorola.
1990's Digital signal processing of all telecommunication equipment (including ISDNs and HDTV) A television can now be used as a television, telephone, computer and video game center all in one place.