- c. 35,000 BCE: The Lebombo bone (a baboon's fibula with notches) is created, representing a possible early mathematical artifact or tally stick.
- c. 20,000 BCE: The Ishango bone is created in Central Africa, featuring a series of notches thought to be a Paleolithic tally system or lunar calendar.
- c. 2700–2300 BCE: The Roman abacus (and its early variants) is used in Babylonia for arithmetic tasks.
- c. 150–100 BCE: The Antikythera mechanism is constructed in the Hellenistic world, serving as an advanced analog computer designed to track astronomical positions and eclipses.
- c. AD 10–70: Hero of Alexandria creates mechanical devices, automata, and programmable carts in Roman Egypt.
- c. AD 850: The Banū Mūsā brothers describe a steam-powered automatic flute in the Book of Ingenious Devices, widely considered one of the earliest descriptions of a programmable device.
- c. AD 1000–1206: Muslim engineers like Al-Biruni, Al-Zarqali, and Ismail al-Jazari invent various astronomical analog computers, planetariums, and complex hydropowered mechanical clocks (such as al-Jazari's castle clock).
- c. 1300s: Ramon Llull invents the Lullian Circle, a notional machine using logical combinatorics to calculate answers to philosophical questions—serving as a founding concept in information science.
- c. 1614: Scottish mathematician John Napier discovers logarithms, publishing tables and creating "Napier's bones," an abacus-like device simplifying multiplication and division.
- c. 1620s–1630: The slide rule is invented by Edmund Gunter and later refined by William Oughtred into a modern circular and linear slide rule for fast mathematical calculations.
- c. 1623: German polymath Wilhelm Schickard designs and builds a machine combining a mechanized form of Napier's rods with the world's first mechanical adding machine (though it was destroyed by fire soon after).
- c. 1642: Blaise Pascal invents the Pascaline (Pascal's calculator), a mechanical calculator utilizing gears to perform addition and subtraction. He builds roughly 20 prototypes/units over the next decade.
- c. 1672: Gottfried Wilhelm von Leibniz invents the stepped reckoner using his famous stepped drum mechanism, aiming to handle multiplication and division via a moveable carriage. He also formally describes the binary numeral system.
- c. 1804: Joseph Marie Jacquard develops an automated loom controlled by paper tape created from punched cards, a massive landmark in mechanical programmability.
- c. 1820: Charles Xavier Thomas de Colmar creates the Thomas Arithmometer, the first commercially successful, mass-produced mechanical calculator.
- c. 1880s–1890: Herman Hollerith invents data storage using punched cards along with a tabulator and keypunch machine, successfully processing the 1890 United States Census in record time. (His enterprise later evolved into IBM).
- c. 1930s: Desktop mechanical calculators capable of addition, subtraction, multiplication, and division are mass-produced by companies like Friden, Marchant, and Monroe.
- c. 1935: The U.S. establishes Social Security, employing large-scale IBM punched-card accounting systems to handle records for 26 million workers.
- c. 1948: The Curta calculator is introduced by Curt Herzstark—a revolutionary, small, hand-cranked pocket mechanical calculator descended from Leibniz's stepped reckoner.
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