What is an object in js

Objects in JavaScript are non-primitive data types that store and organize related data and can represent entities or concepts in the real world. They consist of collections containing key-value pairs, where the keys are strings. Objects can be created using literal syntax or constructors, and their properties can be accessed through dot or square bracket notation. Objects can also store methods (functions) as key-value pairs that are used to perform specific operations or modify internal state.

What are objects in JavaScript?

Objects are non-primitive data types used in JavaScript to store and organize related data. It is a collection of key-value pairs, where the key is a string and the value can be any valid JavaScript value such as a string, number, array or even other object.

Characteristics of objects:

• Used to represent entities or concepts in the real world.
• Can contain multiple types of data.
• Keys must be unique strings.
• The value can be any JavaScript value, including other objects.
• Objects can be accessed using dot or square bracket notation.

Create objects:

You can create objects using two methods:

• Literal syntax : Directly define a collection of key-value pairs. For example:

  <code>const person = {
  name: "John Doe",
  age: 30,
  email: "johndoe@example.com"
  };</code>

• Constructor: Use the new keyword and constructor to create an object. A constructor is a special type of function responsible for creating and initializing objects. For example:

  <code>function Person(name, age, email) {
  this.name = name;
  this.age = age;
  this.email = email;
  }
  
  const person = new Person("John Doe", 30, "johndoe@example.com");</code>

Access object properties:

• Dot mark (.): Used when the key is a valid JavaScript identifier. For example:

  <code>console.log(person.name); // "John Doe"</code>

• Square bracket notation ([]): Used when the key is not a valid JavaScript identifier or the key contains special characters. For example:

  <code>const key = "address";
  console.log(person[key]); // "123 Main Street"</code>

Object methods:

Objects can store methods (functions) in the form of key-value pairs. Methods can perform specific operations and access or modify an object's internal state. The method's key can be any valid JavaScript identifier. For example:

<code>const person = {
  name: "John Doe",
  age: 30,
  greet: function() {
    console.log(`Hello, my name is ${this.name} and I am ${this.age} years old.`);
  }
};

person.greet(); // "Hello, my name is John Doe and I am 30 years old."</code>

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