3000 B.C. The abacus is invented in China.
1836 Charles Babbage designs and begins work on a mechanical computing machine, called an analytical engine.
1843 Ada Lovelace was the first programmer.
1854 George Boole invents Boolean algebra, which would form the foundation for digital computer design.
1886 Herman Hollerith invents the first electromechanical card sorter.
1906 Lee DeForest invents the vacuum tube.
1919 W. H. Eccles and F.W. Jordan invent the flip-flop, capable of storing binary information.
1924 IBM (International Business Machine Corporation) is founded in 1924. Here is the 80 column paper punch card developed by IBM.
1932 G. Taushek invents the magnetic drum.
1938 John V. Atanasoff and Clifford Berry invent the first digital computer using vacuum tubes.
1943 John Von Neumann realizes the advantages of storing both data and computer instructions as binary data. He introduces conditional branching as a computer instruction. Computers won't be built to take advantage of these innovations until 1947.
1944 The MARK I computer, designed by Howard Aiken, is finished. It weighs 5 metric tons and fills an entire room. It uses paper tape for data and program instruction storage.
1946 The ENIAC computer begins operation at the University of Pennsylvania. It contained 17,500 vacuum tubes, 70,000 resistors, 10,000 capacitors, 1,500 relays, 6,000 manual switches and 5 million soldered joints.
1946 John Tukey first uses the term bit for binary digit.
1948 William Shockley invents the transistor. Here is a diagram showing the operation of a transistor.
1951 Magnetic core memory is invented at Wang Labs.
1953 Bell Telephone Laboratories built the first completely transistorized computer, the TRADIC.
1961 Leonard Kleinrock publishes the first paper on packet switching theory.Packet switching means a dedicated connection is not used for all packets. The data to be sent over the internet means that the data is split up into packets of roughly 1 kilobyte each. Then, each packet is sent from the sender to the destination over the least congested route. This means that not all packets are sent over the same route. When all of the packets have arrived at the destination, they are reassembled into the correct order and the page or other information is displayed. If any packets are missing, the software at the destination requests the sender software to resend them.
1963 Engineers at IBM invent the ASCII coding system. ASCII means American System for Computer Information Interchange.
1969 The ARPAnet, predecessor to the internet, is built. It consists of four nodes at UCLA, Stanford, UCSB, Utah U. Here is the original network diagram from historical archives. This is a map of the ARPANET in 1980.1974 The floppy disk is invented.
1975 The Microsoft company is founded by Bill Gates.
1991 Tim Berners-Lee of CERN releases HTML (Hypertext Markup Language).
1991 The Java language was created at Sun Microsystems. It was officially released to the public in 1995.
1993 The Mosaic internet browser was released for HTML files. Mosaic was developed by Marc Andreessen at Illinois U. NCSA.
1994 The internet has grown to 25 million users. Here is a graph showing the growth in the number of internet hosts over time.
1994 Leonard Adleman invents an artificial biochemical computer.
1995 Javascript was created to make Web programming accessible to non-Java programmers. It was originally called LiveScript.
1999 Companies spend billions of dollars updating their computer systems to make them Y2K Compliant.
2002 A quantum computer is built. Quantum computers, if successful, will solve certain difficult problems much faster than conventional computers.