Working with Numbers

All numbers in JavaScript are 64-bit floating-point values. Unlike other languages, there is no internal differentiation between floating-point values and integers. JavaScript provides several objects containing functions that are orientated specifically around floating-point values and integers. However, these objects are semantic. Therefore, applying integer-specific functions to a number will still result in a floating-point value.

Numbers are the simplest form of data represented by the JavaScript engine. Number values are immutable, which means their value cannot be modified in memory. If you assign a new number to a variable, you are simply overwriting the old value with the new. The existing value is not modified.

Since numbers are passed to variables by value, it is not possible for two variables to point to the same number address space. Therefore, working with number values is considered pure, providing you do not reassign values to variables.

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