Early Computing Timeline
The Slide Rule
The slide rule, also known colloquially in the United States as a slipstick, is a mechanical analog computer. The slide rule is used primarily for multiplication and division, and also for functions such as exponents, roots, logarithms and trigonometry, but typically not for addition or subtraction. It was Oughtred who first used two such scales sliding by one another to perform direct multiplication and division; and he is credited as the inventor of the slide rule in 1622.
The Step Reckoner
The step reckoner (or stepped reckoner) was a digital mechanical calculator invented by the German mathematician Gottfried Wilhelm Leibniz around 1673. This machine was invented so that people could more easily and readily multiply and divide.
The Difference engine
A difference engine created by Charles Babbage invented somewhere between 1791-1871 is an automatic mechanical calculator designed to tabulate polynomial functions. Its name is derived from the method of divided differences, a way to interpolate or tabulate functions by using a small set of polynomial coefficients.
The Analytical Engine
The Analytical Engine was a proposed mechanical general-purpose computer designed by English mathematician and computer pioneer Charles Babbage. It was first described in 1837 as the successor to Babbage's difference engine, a design for a simpler mechanical computer. The Analytical Engine was created to try to revolutionize computers in the early to mid 1800's.
The abacus, also called a counting frame, is a calculating tool that was in use in Europe, China and Russia, centuries before the adoption of the written Hindu–Arabic numeral system. The exact origin of the abacus is still unknown. Today, abacuses are often constructed as a bamboo frame with beads sliding on wires, but originally they were beans or stones moved in grooves in sand or on tablets of wood, stone, or metal. no known date of invention that I can find but was definitely used in ancient times.
The astrolabe is an elaborate inclinometer, historically used by astronomers and navigators to measure the altitude above the horizon of a celestial body, day or night. Invented by Abd al-Rahman al-Sufi. The Astrolabe was invented to measure altitude.
The tabulating machine was an electromechanical machine designed to assist in summarizing information stored on punched cards. Invented by Herman Hollerith, the machine was developed to help process data for the 1890 U.S. Census. The tabulating machine was invented to try to further enhance and revolutionize technology.
ENIAC was amongst the earliest electronic general-purpose computers made. It was Turing-complete, digital and able to solve "a large class of numerical problems" through reprogramming. ENIAC was completed in 1945 and first put to work for practical purposes on December 10, 1945. J. Presper Eckert and John Mauchly were the two who worked profusely to build this computer which helped pave the way for todays tech.