A mechanical computer is built from mechanical

Machine

A machine manages power to accomplish a task, examples include, a mechanical system, a computing system, an electronic system, and a molecular machine. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work...

 components such as lever

Lever

In physics, a lever is a rigid object that is used with an appropriate fulcrum or pivot point to either multiply the mechanical force that can be applied to another object or resistance force , or multiply the distance and speed at which the opposite end of the rigid object travels.This leverage...

s and gears, rather than electronic

Electronics

Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

 components. The most common examples are adding machine

Adding machine

An adding machine was a class of mechanical calculator, usually specialized for bookkeeping calculations.In the United States, the earliest adding machines were usually built to read in dollars and cents. Adding machines were ubiquitous office equipment until they were phased out in favor of...

s and mechanical counters, which use the turning of gears to increment output displays. More complex examples can carry out multiplication and division, and even differential analysis

Differential analyser

The differential analyser is a mechanical analogue computer designed to solve differential equations by integration, using wheel-and-disc mechanisms to perform the integration...

.

Mechanical computer

Computer

A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

s reached their zenith during World War II, when they formed the basic of complex bombsight

Bombsight

A bombsight is a device used by bomber aircraft to accurately drop bombs. In order to do this, the bombsight has to estimate the path the bomb will take after release from the aircraft. The two primary forces during its fall are gravity and air drag, which makes the path of the bomb through the air...

s including the Norden

Norden bombsight

The Norden bombsight was a tachometric bombsight used by the United States Army Air Forces and the United States Navy during World War II, and the United States Air Force in the Korean and the Vietnam Wars to aid the crew of bomber aircraft in dropping bombs accurately...

, as well as the similar devices for ship computations such as the US Torpedo Data Computer

Torpedo Data Computer

The Torpedo Data Computer was an early electromechanical analog computer used for torpedo fire-control on American submarines during World War II . Britain, Germany, and Japan also developed automated torpedo fire control equipment, but none were as advanced as US Navy's TDC...

 or British Admiralty Fire Control Table

Admiralty Fire Control Table

thumb|Admiralty Fire Control Table in the transmitting station of [[HMS Belfast |HMS Belfast]].The Admiralty Fire Control Table was an electromechanical analogue computer fire-control system that calculated the correct elevation and deflection of a Royal Navy cruiser or battleships' main armament,...

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