**Infinity** is a mathematical concept that refers to a quantity without a bound.

The **JavaScript Infinity property** is a global property representing infinity. The initial value of `Infinity`

is `Number.POSITIVE_INFINITY`

. `Infinity`

is greater than any other number, including itself.

Infinity usually occurs when the result of an operation is impossible to represent because it is *too large* or *too small* to fit into a float. As a value, `Infinity`

indicates **division by zero** or an **arithmetic overflow** or **underflow**, for example when the exponent of a floating point number is too large:

`Math.pow(2, 1024); // Infinity`

Although arithmetically undefined, division by zero in JavaScript is valid and has well-defined results^{1}:

- 1 / 0 yields
`Infinity`

- (-1) / 0 yields
`-Infinity`

- 0 / 0 yields
`NaN`

As a result, JavaScript will not throw an error when dividing by zero so it is up to the programmer to check whether the divisor of a fraction is not 0.

The `isFinite`

function can be used to check if a given value is a finite number.

- ^ JavaScript uses the IEEE 754 standard to perform all of its arithmetic operations

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