differential analyzer, electromechanical analog computing device used in the early and mid-20th century for solving differential equations. Its principal components performed the mathematical operation of integration (see also integrator).
The American electrical engineer Vannevar Bush and others at the Massachusetts Institute of Technology invented the first continuous integraph, later called a differential analyzer, during the early 1930s. Its integrators consisted of replaceable shafts, gears, wheels, and disks and required much manual setting up. The differential analyzer was replaced by the digital computer in the 1950s.