The first calculating machine in data processing was

The first calculating machine in data processing was the abacus. An abacus is a simple device used for arithmetic calculations. It consists of a frame with rods and beads, where each bead represents a number. By moving the beads on the rods, one can perform arithmetic calculations such as addition, subtraction, multiplication, and division. The abacus was used for centuries and was widely used in many parts of the world before the invention of modern electronic calculators and computers.