An electronic differential analyzer capable of solving ordinary differential equations of orders through the sixth, both linear and nonlinear, is described. This analyzer has a high speed of operation and is extremely flexible with regard to equation parameters and initial conditions. This flexibility permits rapid investigation of wide ranges of equation solutions with regard to periodicity, instability, and discontinuities. It renders practicable the solution of endpoint boundary-value problems, that is, problems in which the final rather than initial values are specified.