But question asks how many total bytes does the ENIAC register memory occupy — answer = 200

Wed, 29 Apr 2026 19:12:07 +0000

How Many Total Bytes Did the ENIAC Register Memory Occupy? Understanding the Historical Basics (Answer: 200 Bytes) When exploring the pioneering world of early computing, one of the most frequently asked questions centers on the storage capacity of foundational machines—specifically, how many total bytes did the ENIAC’s register memory occupy? The answer is 200 bytes. But this simple figure opens the door to a deeper appreciation of how early computer architecture shaped modern computing. ### What Was ENIAC and Its Memory Capacity? The ENIAC (Electronic Numerical Integrator and Computer), completed in 1945 at the University of Pennsylvania, was a revolutionary machine—one of the first general-purpose electronic digital computers. Unlike today’s gigabyte- or terabyte-scale memory systems, ENIAC’s memory was analog and mechanical by design, relying on over 20,000 vacuum tubes and electromechanical switches. Its “register memory”—the high-speed internal storage used for temporary data holding during calculations—occupied a modest but critical space: exactly 200 bytes.