The equals sign or equality sign (=) is a mathematical symbol used to indicate equality.

The etymology of the word "equal" is from the Latin word "æqualis" as meaning "uniform", "identical", or "equal", from aequus ("level", "even", or "just").

The "=" symbol that is now universally accepted in mathematics for equality was first recorded by Welsh mathematician Robert Recorde in The Whetstone of Witte (1557). The original form of the symbol was much wider than the present form.

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