JavaScript Data Types

JavaScript is a dynamically typed language, which means that variables do not have their data types explicitly defined. Rather, the data type is decided upon during runtime. Primitive types and object types are the two primary categories into which JavaScript's built-in data types fall.

Primitive Data Types

Number:

Represents both integers and floating-point numbers.

let integerNumber = 42;
let floatNumber = 3.14;

String:

Represents a sequence of characters.

let message = "Hello, World!";

Boolean:

denotes a logical value that can be true or false.

let isTrue = true;
let isFalse = false;

Null:

Symbolizes the deliberate removal of all object value.

let nullValue = null;

Undefined:
Represents an uninitialized or undefined value.

let undefinedValue;

Symbol:
Introduced in ECMAScript 6, represents a unique identifier.

let sym = Symbol("description");

Object Data Type:

Object:
Represents a collection of key-value pairs.

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

Special Data Types:

Function:
Functions are a special type of object that can be invoked.

function add(a, b) {
  return a + b;
}

Array:
An object that holds an ordered collection of values.

let numbers = [1, 2, 3, 4, 5];

Date:
Represents a date and time.

let currentDate = new Date();

RegExp:
Represents a regular expression for pattern matching.

let pattern = /[a-z]+/;

Understanding and working with these data types is fundamental to writing effective JavaScript code. Keep in mind that JavaScript's dynamic typing allows variables to change their data type during runtime, which can be both powerful and challenging depending on the context.