The relative merits of incremental and conventional digital computers in air-borne real-time control

In the conventional or general-purpose digital computer, operands are transferred in their entirety from one functional block to another. The inputs and outputs of such a block are simply the values of the constants and variables concerned. In the incremental computer, however, only portions of the operands are transferred. The inputs and outputs of a functional block are increments of the quantities concerned; the digital differential analyzer is one example.1