Term of the Moment
application suite
Definition: Differential Analyzer
An analog calculator built in the 1930s by Vannevar Bush at MIT. Designed to solve differential equations, the Differential Analyzer was used in World War II to calculate ballistics tables that showed the trajectory of a projectile over distance. Containing more than a thousand gears, the machine took up an entire room. It was tediously programmed by physically changing the gears with a screwdriver and wrench, and the output was displayed as graphs.
Bush and His Differential Analyzer
Although programmed with a screwdriver and wrench, Bush's machine was a breakthrough for its time, and about a dozen Analyzers were built. As the gears wore over time, the machine introduced inaccuracies, yet it was the fastest computational tool of its kind. (Image courtesy of The Computer History Museum.)