Introduction

The following is a brief (and incomplete) overview of some of the important historical events in the history of computing.

The Mechanical Era

YearPersonEvent
1642 Blaise Pascal Created a machine that could add and subtract numbers. Dials were used to enter the numbers. It also correctly handled carries, such as when the numbers 19 and 13 are added. The machine would produce the correct answer of 32 since it correctly carried the 1 from adding 9 and 3.
1801 Joseph-Marie Jacquard Created a machine called the Jacquard Loom that ushered in the era of mechanization in textile production. It used punched cards to control the patterns of the textiles being weaved. It also led to riots in France by workers fearful of losing their jobs.
1822 Charles Babbage Designed a machine called the Difference Engine whose goal was to automatically calculate entries in navigation and other tables in order to produce these tables more quickly and with fewer errors. It was never fully completed due to its complexity and the fact that Babbage lost interest when he came up with a better idea.
1833 Charles Babbage Designed a machine called the Analytical Engine. The design had all the basic components of a modern day computer. In addition, it was designed to be programmable using punched cards. This way, it could perform many tasks, not just a single task like calculating entries for tables. Though never fully completed, Babbage is still called the "Father of the Computer". He had the right ideas, but the technology of the time was not advanced enough for him to fully realize those ideas.
1833 Ada Lovelace Charles Babbage's assistant. She wrote programs for the Analytical Engine using punched cards. Considered the world's first programmer.
1890 Herman Hollerith Created a punched card tabulating machine for use in the 1890 U.S. Census. It was very successful and Hollerith went on to form the company that became IBM.

The Electronic Era (With Vacuum Tubes)

YearPersonEvent
1943 ENIAC, the first large scale electronic computer, is built. Weighing several tons and taking up a large room, it had less computing power than modern-day calculators.
1945 The first computer bug is found. It is a moth that got caught in a mechanical relay, causing the computer to malfunction. The term bug has been used ever since to indicate a problem with computer software.
1953 IBM produces its first computer. Though joining the computer business late, by the end of the decade, it would be the largest computer company by far.

The Electronic Era (With Integrated Circuits)

YearPersonEvent
1960 The integrated circuit (aka chip) is invented, replacing vacuum tubes in computers. This allows faster, more reliable, and more powerful computers to be built, while at the same time greatly reducing computers' sizes and cost.
1969 Work begins on the ARPAnet, the pre-cursor to the Internet. Funded by the U.S. Department of Defense, the goal is to build a network that could remain operational even if part of it was destroyed by a nuclear attack. The Advanced Research Projects Agency headed up the project.
1973 Bob Metcalf Invents Ethernet, which is the foundation for local area networking.
1976 Microsoft and Apple founded. The Apple II, the first commercial personal computer, is released.
1978 Visicalc is released for the Apple II. It is the first business software produced.
1981 The IBM-PC personal computer is released.
1984 The Macintosh, the first commerical GUI personal computer, is released.
1990-1991 Tim Berners-Lee Creates the World Wide Web to make it easier to share information across the Internet.
Mid-to-late 1990's Access to the Internet and the World Wide Web expand exponentially.