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DIGITAL SIGNALS Alec Reeves develops pulse-code modulation system in 1939 for converting analog information into digital style on-and-off signals
1945 Science-fiction writer Arthur C. Clarke proposes geostationary satellites to aid communications
TRANSISTOR William Shockley, Walter Brattain and John Bardeen invent the transistor at Bell Labs in 1947
The laser in invented at Bell Labs in 1958
1960 AT&T introduces Touch-Tone dialing
1962 Launch of the first communications satellite, Telstar
Ericsson introduces its first cellular phone in 1979
1979 CompuServe launches its online service launches
1988 PanAmSat launches the first privately owned communications satellite
COMPUTING
After Herman Hollerith designs his punch-card tabulating machine for the 1890 U.S. Census and founds the company that will become IBM, the idea of computers slowly gathers steam
1919 Hugo Koch patents a "secret writing machine," later known as the Enigma, a mechanical, cryptography device used by Germany during World War II
Birth of Computers
1932 M.I.T.'s Vannevar Bush builds Differential Analyzer, a mechanical computer
1936 Britain's Alan Turing publishes description of a universal computing machine
1939 First computer that uses vacuum tubes built by John Atanasoff
1943 Turing and other Enigma-code crackers at Bletchley Park build Colossus
1945 John Mauchly and J. Presper Eckert build ENIAC, the first fully electronic computer
In 1949 Claude Shannon shows that all information can be reduced to 1's and 0's
1951 Mauchly and Eckert create UNIVAC, the first commercial computer; a year later, it successfully predicts a landslide for Eisenhower
MICROCHIP In 1958 Jack Kilby and Robert Noyce independently invent the microchip
1964 IBM launches the System/360 the first commercial mainframe computer
1969 Bell Labs creates Unix, an operating system that works across computer platforms
1974 The first personal computer kit, the Altair 8800, goes on sale for $439
1977 Steve Jobs and Steve Wozniak develop the Apple II
1981 IBM PC is Launched, using software from Bill Gates' Microsoft
1984 Apple, with a little help from Xerox PARC, releases the Macintosh
INTERNET
ARPA After Sputnik, Eisenhower in 1957 forms the Advanced Research Project Agency to coordinate research
1961 M.I.T. starts "time-sharing" computers, allowing several users to access one machine simultaneously
In 1964 Paul Baran of Rand Corp. calls for computer-based communications system that could survive a nuclear war
1967 Donald Davies devises "packet switching" as a way to route information through networks
1969 The ARPA Net--a network of university computers--is born
1974 Vinton Cerf and Robert Kahn design Transmission Control Protocol (TCP) for Linking different computer networks
1978 Programmer Ward Christensen writes MODEM (modulator-demodulator), allowing PCs to talk over public phone lines
1985 ARPA Net renamed the Internet
THE WEB Tim Berners-Lee creates an Internet protocol called the World Wide Web in 1990