In 240 B.C. – Greek astronomer, geographer, mathematician and librarian in Alexandria, Eratosthenes calculated the Earth’s circumference. His data was based on the length of shadows in different locations and simple geometry, but his calculations were not far wrong.

In 1623 – Mathematician Blaise Pascal was born in France. He invented a digital calculator, the Pascaline, to help his father in his tax-collecting work.

In 2003 – Apple released dock connector-to-USB 2.0 cables and drivers for third-generation iPods. Previous iPods had been FireWire only.

Like Tech History? Purchase Tom Merritt’s Chronology of Tech History at Merritt’s Books site.

In 1908 – Scottish electrical engineer, Alan Archibald Campbell-Swinton, published a brief letter in the journal Nature, describing the essentials of making and receiving television images. He described using an electron gun in the neck of a cathode-ray tube to shoot electrons toward the flat end of the tube, which was coated with light-emitting phosphor. Others like Farnsworth and Baird would make just such devices years later.

In 2002 – Kevin Warwick had his chip removed. Warwick implanted the chip earlier that year in order to experiment with human-computer interaction, culminating in a direct connection to his wife.

In 2009 – The Lunar Reconnaissance Orbiter (LRO), a NASA robotic spacecraft was launched on its mission to collect information about the Moon, particularly around the poles.

Like Tech History? Purchase Tom Merritt’s Chronology of Tech History at Merritt’s Books site.

In 1936 – Edwin Armstrong presented FM radio at FCC headquarters. Armstrong played a jazz record over conventional AM radio, then switched to an FM broadcast. “[I]f the audience of 50 engineers had shut their eyes they would have believed the jazz band was in the same room.”

In 1946 – The first mobile telephone call was made from a car in St. Louis, Missouri.

In 1997 – Programmers deciphered code written in the impenetrable Data Encryption Standard, the strongest legally exportable encryption software in the United States. The hackers organized over the Internet and cracked the software in five months, proving that stronger encryption was needed.

Like Tech History? Purchase Tom Merritt’s Chronology of Tech History at Merritt’s Books site.

In 1911 – The Tabulating Company (founded by Herman Hollerith), the Computing Scale Company, and the International Time Recording Company merged to form the Computing-Tabulating-Recording Company in Endicott, New York. They would later change the company name to International Business Machines,and later just IBM.

In 1963 – Soviet Cosmonaut Valentina Tereshkova became the first woman to fly in space, orbiting the Earth 48 times.

In 1977 – Software Development Laboratories was incorporated in Redwood Shores, California, by Larry Ellison, Bob Miner and Ed Oates. They later came up with the catchier name, Oracle.

Like Tech History? Purchase Tom Merritt’s Chronology of Tech History at Merritt’s Books site.

In 1878 – Photographer Eadweard Muybridge used high-speed photography to capture a horse’s motion. The photos showed the horse with all four feet in the air during some parts of its stride. Stop-motion photography was born.

In 1949 – Jay Forrester wrote down a proposal for core memory in his notebook. Core memory was the standard for computer memory until advances in semiconductors in the 1970s.

In 1987 – Compuserve’s Sandy Trevor and his team, which included inventor Steve Wilhite, released GIF version 87a. The new enhanced format allowed people to create compressed animations. “Under Construction” GIFs everywhere became possible.

Like Tech History? Purchase Tom Merritt’s Chronology of Tech History at Merritt’s Books site.