And the Asian abacus remains so efficient that its purely mental form (in Japan, anzan) is faster than any electronic calculator.

FORBES: Humanity's Unseen Weapons

On May 6th, 1949 EDSAC (or Electronic Delay Storage Automatic Calculator) ran its first programs, calculating a table of squares and generating a list of prime numbers.

ENGADGET

To see how much you could reduce your environmental impact by switching to electronic billing, Payitgreen.org offers this calculator.

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