JavaScript Data types

In JavaScript, there are two main types of data: primitive data types and objects data types.

primitive: Primitive data types are simple data types that represent a single value. The primitive data types in JavaScript are: String, Number, Boolean, Null, Undefined.

To check the data type of a value in JavaScript, you can use the typeof operator. The typeof operator returns a string that represents the type of the value.

console.log(typeof "world");
//It will display String in the browser's console.
console.log(typeof 144);
//It will display Number in the browser's console.
console.log(typeof true);
//It will display Boolean in the browser's console.

In JavaScript, strings are immutable, which means that you cannot modify individual characters of a string.

let name = "John";
name = "Jane"; // allowed
name[0] = "J"; // not allowed

In this example, the name variable is assigned the value John, which is a string. The value of the name variable can be changed by assigning a new value to it (e.g. name = "Jane"). However, you cannot change the individual characters of the string directly.

Objects: Objects are complex data types that can contain multiple values and properties. Objects are used to represent real-world entities or abstract concepts with multiple characteristics. Objects are created using the syntax and can contain multiple properties, which are represented as key-value pairs. For example:

let person = {
  firstName: "John",
  lastName: "Doe",
  age: 30,
  isEmployed: true,
};

In this example, the person object has four properties: firstName, lastName, age, and isEmployed. Each property has a key (the property name) and a value (the property value).

console. console.log(person["lastName"]); //It will display Doe in the browser's
console. ```
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  Objects are mutable, which means that you can change their properties and
  values at any time.
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