ENIAC 1946

As in many other first along the road of technological progress, the stimulus which initiated and sustained the effort that produced the ENIAC (electronic numerical integrator and computer)--the world's first electronic digital computer--was provided by the extraordinary demand of war to find the solution to a task of surpassing importance. To understand this achievement, which literally ushered in an entirely new era in this century of startling scientific accomplishments, it is necessary to go back to 1939

Programmed by plugging in cords and setting thousands of switches, the decimal-based machine used 18,000 vacuum tubes, weighed 30 tons and took up 1,800 square feet. It cost a fortune in electricity to run; however, at 5,000 additions per second, it was faster than anything else. Initially targeted for trajectory calculations, by the time it was ready to go, World War II had ended. Soon after, it was moved to the army's Aberdeen Proving Grounds in Maryland where it was put to good work computing thermonuclear reactions in hydrogen bombs and numerous other problems until it was dismantled in 1955.

The function of the machine was split into eight basic circuit components: the accumulator, initiator, master programmer, multiplier, divider/square-root, gate, buffer, and the function tables. The accumulator was the basic arithmetic unit of the ENIAC. It consisted of twenty registers, each ten digits wide, which performed addition, subtraction, and temporary storage. The accumulator can be compared to the registers in today's central processing units.

ENIAC proved that the thinking behind electronic computing was sound, and smaller and faster machines were forecast at the dedication ceremony. However, it is doubtful they would have conceived that the entire CPU would be no bigger than a pencil eraser some day.

By: Amanda Raad