A historian analyzing early computer blueprints finds that the ENIAC used 20 decimal digits of memory per register and had 10 registers. Later, a STOR-MATAC system improved this to 16 binary registers (2 bytes each) for the same effective capacity. How many total bytes does the ENIAC register memory occupy compared to the improved system?

Tue, 05 May 2026 14:20:35 +0000

From Decimal Digits to Binary Bytes: Understanding Early Computer Memory Systems — A Historical Comparison of ENIAC and STOR-MATAC In the foundational decades of computing, engineers faced the challenge of representing and storing complex numerical data efficiently. A striking example lies in the contrast between two early computer architectures: the ENIAC and its successor-inspired conceptual evolution in the STOR-MATAC system. ### ENIAC: Decimal-Based Register Memory During the 1940s, the ENIAC (Electronic Numerical Integrator and Computer) pioneered electronic computation with a radical architecture for its time. As detailed by historians reviewing original blueprints, ENIAC used 20 decimal digits (decits) per register. Each register stored a full decimal value, with no binary conversion involved in raw memory access.