developer-roadmap/src/data/roadmaps/javascript/content/number@GZ_SXsWmP7AsXRTc4WUMw.md

number

The Number data type in JavaScript represents floating-point numbers, such as 37 or -9.25. The Number constructor provides constants and methods to work with numbers, and values of other types can be converted to numbers using the Number() function.

Example

let num1 = 255; // integer
let num2 = 255.0; // floating-point number with no fractional part
let num3 = 0xff; // hexadecimal notation
let num4 = 0b11111111; // binary notation
let num5 = 0.255e3; // exponential notation

console.log(num1 === num2); // true
console.log(num1 === num3); // true
console.log(num1 === num4); // true
console.log(num1 === num5); // true

In this example:

• 255 and 255.0 are equivalent, as JavaScript treats both as the same number.
• 0xff represents 255 in hexadecimal notation.
• 0b11111111 represents 255 in binary notation.
• 0.255e3 is 255 in exponential notation.
• All these different representations are equal to 255 in JavaScript.