Javascript Operators

Operators in javascript , just like in any other programming language, are symbols used to perform operations on values and variables. These help us with -

• simple arithmetic operations , assigning values

• logical operations, bit-level operations etc.

Some operators such as arithmetic and bitwise operators, are common across many languages.

Assignment Operators -

these help us assign values to variables

let a = 2;
let b = 4;

add / subtract and assign

+= adds a value to the variable and then assigns the result back to it

Similarly , -= will subtract value from variable and assign result back.

let a = 2;

a += 3;   // same as: a = a + 3
console.log(a);  // 5

let b = 4;

b -= 1;   // same as: b = b - 1
console.log(b);  // 3

Arithmetic Operators -

These allow us to perform mathematical operations such as addition, subtraction, multiplication, division, and finding the remainder.

let a = 2;
let b = 4;

console.log(a + b); // 6  
console.log(b - a); // 2  
console.log(a * b); // 8  
console.log(b / a); // 2  
console.log(a % b); // 2  

Comparison Operators -

as the name suggests , these operators are used in comparison of values and return us with boolean values (true / false)

let a = 2;
let b = 4;

console.log(a == b);   // false
console.log(a != b);   // true  (Not equal)

console.log(a < b);    // true
console.log(b > a);    // true  (Greater than)

! - NOT operator

Strict comparison

=== is the strict equality operator. It compares both the value and the data type.

let a = "1";
let b = 1;

console.log(a == b);   // true
console.log(a === b);  // false

• == converts the string "1" into a number before comparing (type coercion)

• === does not convert types, so "1" (string) and 1 (number) are different

• !== Strict not equal (compares value and type)

Logical Operators -

used to combine or modify boolean expressions, they return either true or false.

JavaScript provides three main logical operators:

• && - AND , Both conditions must be true

• || - OR , At least one condition must be true

• ! - NOT , Reverses the result

let a = 2;
let b = 4;
let c = 6;

let sum = a + b;

console.log(true && true);   // true
console.log(true && false);  // false

console.log(true || true);   // true
console.log(true || false);  // true

The NOT ! operator helps us write a condition in reverse.
It flips the result — true becomes false, and false becomes true.

console.log(!true);   // false
console.log(!false);  // true

with conditions

let a = 2;
let b = 4;

console.log(!(a > b));  // true

Logical operators are often combined with comparison operators:

console.log(sum != c);           // false (6 is equal to 6)
console.log(sum == c && true);   // true
console.log(a < b && b < c);     // true