JS Operators

What are Operators?

Operators are symbols that perform operations on values and variables. JavaScript includes arithmetic, assignment, comparison, logical, and more.

Arithmetic Operators

Arithmetic operators are used for basic math operations.

let a = 10;
let b = 3;

console.log(a + b); // 13
console.log(a - b); // 7
console.log(a * b); // 30
console.log(a / b); // 3.333...
console.log(a % b); // 1 (remainder)
console.log(a ** b); // 1000 (power)

Increment and decrement are common in loops and counters.

let x = 5;

x++;
console.log(x); // 6

x--;
console.log(x); // 5

Assignment Operators

Assignment operators set or update a variable value.

let n = 10;

n = 20;
n += 5;  // 25
n -= 2;  // 23
n *= 3;  // 69
n /= 3;  // 23
n %= 5;  // 3

console.log(n);

The += operator is also used for string concatenation.

let name = "Java";
name += "Script";
console.log(name); // JavaScript

Comparison Operators

Comparison operators return true or false. They are used in conditions.

console.log(5 == "5");   // true  (loose equality)
console.log(5 === "5");  // false (strict equality)

console.log(5 != "5");   // false
console.log(5 !== "5");  // true

console.log(10 > 5);     // true
console.log(10 >= 10);   // true
console.log(3 < 2);      // false
console.log(3 <= 3);     // true

Best practice: prefer strict equality === and strict inequality !== to avoid type coercion surprises.

Operator Precedence

Some operators run before others. Use parentheses to make intentions clear.

let result1 = 10 + 2 * 3;     // 16
let result2 = (10 + 2) * 3;   // 36

console.log(result1, result2);

Next Step

Continue with JS If Conditions to use operators inside real decisions.