What does || mean in js

The || operator in JavaScript is a logical OR operator that combines Boolean values, returning a true or false value to the first true operand. This operator follows "short-circuit" evaluation and can be used to assign default values ​​to variables.

|| operator in JS

|| in JavaScript operator is a logical OR operator used to combine two or more Boolean values. Its function is to return a true value when any of the operands is true, otherwise it returns a false value.

Syntax:

<code>x || y</code>

where x and y are Boolean values ​​or operands that can be converted to Boolean values.

Operation rules:

• If x is true, x will be returned.
• If x is false, return y.
• If both x and y are false, return false.

Example:

<code>const a = true;
const b = false;

console.log(a || b); // true
console.log(b || a); // true
console.log(a || a); // true
console.log(b || b); // false</code>

Note:

• || Operation operator has a lower precedence than the && operator.
• The || operator uses "short-circuit" evaluation when comparing the order of operands. If the first operand is true, the second operand is not evaluated. The
• || operator can be used to assign a default value to a variable. For example:

<code>const name = name || "John Doe";</code>

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