12. The Number Type

In JavaScript, the Number type covers both whole numbers (integers) and numbers with decimal points (floats).

Integers

javascript let count = 42; let year = 2024;

Floating Point Numbers (Decimals)

javascript let price = 19.99; let piApproximation = 3.14159;

Arithmetic Operations

Numbers support standard math operations:

javascript let a = 10; let b = 3;

console.log(a + b); // Addition: 13 console.log(a - b); // Subtraction: 7 console.log(a * b); // Multiplication: 30 console.log(a / b); // Division: 3.333... console.log(a % b); // Modulo (Remainder): 1 console.log(a ** b); // Exponentiation: 1000

The Floating Point Problem

Due to how computers store numbers (binary floating-point standard), arithmetic with decimals can sometimes be imprecise (this is true for most programming languages).

javascript console.log(0.1 + 0.2); // Output: 0.30000000000000004 (NOT 0.3)

For financial applications, special libraries or working with cents (integers) is necessary.