Computer

A computer comprising a three-dimensional array of data processing units. The computer has particular application in simulating neural networks in which case the data processing units operate as neuron simulators. Each data processing unit produces the sum of input numbers multiplied by respective coefficients and performs a non-linear operation on the sum to produce an output number. The data processing units have serial data intercommunication links 21-26 between adjacent units along the coordinate axes of the array, the units at the boundary of the array being connected to inputs and outputs. The intercommunication is provided by a shifting register in each unit, the registers of two units being joined end to end in a loop through multiplexers and data in each register being shifted into the other register when data communication between the units is required. A broadcasting means may be provided to enter data and/or instructions into all or selected ones of the data processing units directly.