JSOperators

&

Bitwise AND

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The bitwise and operator takes the left number and ANDs it with the right number. The result is a number with the bits of the left number set to 1 if the same bit is set in both numbers and 0 if it is not.

console.log(2 & 2); // 2
console.log(2 & 3); // 2
console.log(2 & 4); // 0