Operators and Expressions

Operators and expressions are fundamental components of JavaScript that allow developers to perform various operations on data and variables.

Understanding how to use operators and create expressions is essential for writing high-quality and efficient JavaScript code.

This detailed explanation will focus on providing quality information about operators and expressions in JavaScript.

Operators in JavaScript

Operators are symbols or keywords that perform specific operations on one or more values, known as operands. JavaScript supports various operators, including arithmetic, comparison, logical, assignment, and more.

Arithmetic Operators

Arithmetic operators perform basic mathematical operations such as addition, subtraction, multiplication, division, and modulus.

  let a = 5;

  let b = 2;

  let sum = a + b;       // Addition: 5 + 2 = 7

  let difference = a - b;// Subtraction: 5 - 2 = 3

  let product = a * b;   // Multiplication: 5 * 2 = 10

  let quotient = a / b;  // Division: 5 / 2 = 2.5

  let remainder = a % b; // Modulus: 5 % 2 = 1

Comparison Operators

Comparison operators are used to compare values and return a boolean result (true or false) based on the comparison.

  let x = 10;

  let y = 5;

  let isEqual = x === y;    // Strict equality: false

  let isNotEqual = x !== y; // Strict inequality: true

  let isGreater = x > y;    // Greater than: true

  let isLess = x < y;       // Less than: false

  let isGreaterOrEqual = x >= y; // Greater than or equal: true

  let isLessOrEqual = x <= y;    // Less than or equal: false

Logical Operators

Logical operators are used to combine or negate boolean values.

  let isTrue = true;

  let isFalse = false;


  let logicalAnd = isTrue && isFalse; // Logical AND: false

  let logicalOr = isTrue || isFalse;  // Logical OR: true

  let logicalNot = !isTrue;           // Logical NOT: false

Assignment Operators

Assignment operators are used to assign values to variables.

  let num = 10;

  let name = 'John';


  num += 5;    // Equivalent to num = num + 5;

  name += ' Doe'; // Equivalent to name = name + ' Doe';

Expressions in JavaScript

An expression is a combination of values, variables, and operators that can be evaluated to produce a result. Expressions can be simple or complex, playing a vital role in calculating and making decisions in JavaScript.

Simple Expressions

Simple expressions consist of single values or variables.

  let age = 25;

  let name = 'John Doe';

Complex Expressions

Complex expressions involve multiple operators and operands.

  let x = 10;

  let y = 5;


  let result = (x * y) + (y - 2); // 10 * 5 + (5 - 2) = 53

Conditional Expressions (Ternary Operator)

The ternary operator is a concise way to write conditional expressions.

  let isEven = (x % 2 === 0) ? true : false;  

Function Expressions

Functions can be used within expressions and assigned to variables.

let add = function(a, b) {

    return a + b;
};

let sum = add(5, 3); // 5 + 3 = 8