In JavaScript, objects are collections of properties, where each property has a key (also known as a "name") and a value. Objects allow you to store related data and functionality together in a structured way, making them one of the most important and flexible types in JavaScript.

1. Creating an Object

You can create an object using curly braces {} and define key-value pairs within.

let person = {
  name: "Ravi",
  age: 30,
  isStudent: false
};

In this example, person is an object with three properties: name, age, and isStudent.

2. Accessing Object Properties

You can access properties in two ways:

• Dot notation: objectName.property
• Bracket notation: objectName["property"]

console.log(person.name);      // Output: Ravi
console.log(person["age"]);    // Output: 30

3. Adding or Modifying Properties

You can add or update properties using dot notation or bracket notation.

person.city = "Delhi";          // Adds new property 'city'
person.age = 31;                // Updates 'age' property
console.log(person.city);       // Output: Delhi
console.log(person.age);        // Output: 31

4. Deleting Properties

You can remove a property using the delete keyword.

delete person.isStudent;
console.log(person.isStudent);  // Output: undefined

5. Methods in Objects

Objects can have methods, which are functions that belong to an object. Define a method using a function inside the object.

let car = {
  brand: "Toyota",
  model: "Camry",
  start: function() {
    console.log("The car has started.");
  }
};

car.start();  // Output: The car has started.

6. this Keyword