Introduction
`// Single line comment/* Multi-line comment*/`
##### Var Keyword
`var name = "John";`
##### Const Keyword
`const pi = 3.14;`
##### Console
`console.log("Hello, World!");`
##### Let Keyword
`let age = 25;`
##### Variables
`let name = "John";`
##### Numbers
`let x = 5;let y = 3.14;`
##### Strings
`let greeting = "Hello, World!";`
Scopes
##### Block Scope
`if (true) { let x = 5; // Block scope}`
##### Global Scope
`var x = 5; // Global scope`
##### Function Scope
`function myFunction() { var x = 5; // Function scope}`
Operators
##### Arithmetic Operators
`let x = 5 + 2; // Additionlet y = 5 - 2; // Subtraction`
##### Assignment Operators
`let x = 5;x += 2; // x = x + 2`
##### Comparison Operators
`let isEqual = (5 == 5); // true`
##### Ternary Operators
`let result = (5 > 2) ? "True" : "False";`
##### Logical Operators
`let and = true && false; // false`
##### Bitwise Operators
`let bitwiseAnd = 5 & 1; // 1`
Conditionals
##### If-Else Statement
`if (true) { // code} else { // code}`
##### Else-If Statement
`if (x > 10) { // code} else if (x > 5) { // code} else { // code}`
##### Switch Statement
`switch (x) { case 1: // code break; case 2: // code break; default: // code}`
Loops
##### For Loop
`for (let i = 0; i < 5; i++) { // code}`
##### Continue
`for (let i = 0; i < 5; i++) { if (i === 2) { continue; } // code}`
##### Break
`for (let i = 0; i < 5; i++) { if (i === 2) { break; } // code}`
##### While Loop
`let i = 0;while (i < 5) { // code i++;}`
##### For...In Loop
`let object = {a: 1, b: 2};for (let key in object) { // code}`
##### Do...While Loop
`let i = 0;do { // code i++;} while (i < 5);`
##### For...Of Loop
`let array = [1, 2, 3];for (let value of array) { // code}`
Arrays
##### Arrays and Index
`let array = [1, 2, 3];console.log(array[0]); // 1`
##### .Concat() Method
`let newArray = array.concat([4, 5]);`
##### .Push() Method
`array.push(4);`
##### .Fill() Method
`array.fill(0);`
##### .Pop() Method
`array.pop();`
##### .Reverse() Method
`array.reverse();`
Functions
##### Declaring And Calling Function
`function myFunction() { // code}myFunction();`
##### Function With Parameter
`function myFunction(param) { // code}myFunction("argument");`
##### Return Keyword
`function add(a, b) { return a + b;}`
Objects
##### Object
`let object = { key: "value"};`
##### Dot Notation
`object.key = "new value";`
##### Bracket Notation
`object["key"] = "new value";`
Classes
##### Class
`class MyClass { constructor() { // code }}`
##### Class Methods
`class MyClass { myMethod() { // code }}`
Iterators
##### Iterator
`let iterator = array[Symbol.iterator]();`
##### next() Method
`iterator.next();`
Modules
##### Modules
`import { myFunction } from './myModule';`
##### Export Multiple Objects
`export { myFunction, myVariable };`
Promises
##### Promises
`let promise = new Promise((resolve, reject) => { // code});`
##### Catch() Method
`promise.catch(error => { // code});`
##### Finally() Method
`promise.finally(() => { // code});`
Async - Await
##### Async Function
`async function myFunction() { // code}`
##### Await Keyword
`let result = await myFunction();`