Early Computing Presented by Brian Barker and Brycen Ainge

Early Mechanical Computers Abacus (Babylon)  About 2400 BC  Originally lines in sand with pebbles South Pointing Chariot (China)  1115 BC  Wheeled chariot with interchangeable, complex gears  Points South regardless of chariot’s direction  Differential gears ~4,100 years before West

Early Mechanical Computers (Cont.) Pānini (India)  5 th century BC  Grammar of Sanskrit into 3959 rules  Used metarules, transformations, recursions  Computing power of a Turing Machine

Progresses in Math Logarithms  200 – 400 BC Indian mathematicians invented  13 th Century Muslims created logarithm tables  17th Century John Napier used logarithms for computations Spurred progress in calculation tools

Algorithms Brahmagupta  7 th Century  Use of 0 as a decimal digit and placeholder Al-Khwarizm  On The Calculation with Hindu Numerals  Taught how to perform a series of steps to perform a task  “Algorithm” is a derivation of his name

Charles Babbage Lived Inventor of the first programmable computer Invented the Difference Engine and the Analytical Engine

Difference Engine Began in 1822 Made to compute polynomial functions Never completed Differenc Engine No. 2 designed  Finally built Also had a printer  Advanced functionality

Analytical Engine More complex than Difference Engine Used punch cards Advanced features It was Turing Complete Ada Lovelace involved with it

Ada Lovelace Babbage called her the “Enchantress of Numbers” First programmer  Created a program for the analytical engine that could compute a sequence of Bernoulli numbers US DoD developed a programming language in 1983 and named it Ada after her

Alan Turing Lived Father of Computer Science Did a lot of research that has been integral to advancements in computer science Invented the Turing Machine

Turing Machines A basic model of computation Used to solve many theory questions Used in Computability Theory  Halting Problem Turing-completeness is a necessity for computers Church-Turing Thesis: If an algorithm exists, a Turing machine can be made to compute it as well as anything else

Turing Machines (continued) Also used in Computational Complexity theory  Algorithmic complexity bounds  P=NP?

References Menabrea, Luigi Federico; Ada Lovelace (1843). "Sketch of the Analytical Engine Invented by Charles Babbage". Scientific Memoirs 3. With notes upon the Memoir by the Translator The Alan Turing Internet Scrapbook. Turing, A.M., 1936, "On Computable Numbers, with an Application to the Entscheidungsproblem", Proceedings of the London Mathematical Society, Series 2, 42 ( ), pp Hoyle, Michelle A., “History Of Computer Science: Computer History From The Past,” April 2007, DR Gears, “South Pointing Chariot,” December 2005,