An analog computer
An analog computer is a form of computer that uses the continuously-changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.An analog
expressing numbers. Analogue computers are more accurate than digital computers but not fast as digital.
Analog computers are the first computers being developed and provided the basis for the development of the modern digital computers. Analog computers are widely used for certain specialized engineering and scientific applications, for calculation and measurement of analog quantities. They are frequently used to control process such as those found in oil refinery where flow and temperature measurements are important. They are used for example in paper making and in chemical industry. Analog computers do not require any storage capability because they measure and compare quantities in a single operation. Analog computers are especially well suited to simulating dynamic systems; such may be conducted in real time or at greatly accelerated rates, thereby allowing experimentation by repeated runs with altered variables. They have been widely used in simulations of aircraft, nuclear power plants, and industrial chemical processes.