"If my research is correct, the first electronic calculator was sold in England in 1963 by Sumlock Comptometer LTD. It was named the "Anita" and used thousands of discrete components including vacuum tubes (called "valves" in England). It weighed 33 pounds and used Nixie tubes (filament wires shaped like numerals) to display results. ... So who made the first fully-electronic calculator? I think the credit goes to England but I may be wrong."

Bruce Flamm, "The World's First Electronic Calculator -- Who Made It?" The International Calculator Collector, Fall 1996, Issue #14, page 3.

Photo Source: Frank Boehm - Calculators Online

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