# Javascript Intro & Basics

## 1. Variables

``` JAVASCRIPT

// Variables

// CONST
// How do I declare a const variable?

const myBirthday = '24th June 1991'

// LET
// How do I declare a let variable?

let myAge = 27

```

## 2. Datatypes

``` JAVASCRIPT

// Datatypes

let myName = "Matthew Cross"; // String

let myAge = 27; // Number

let myMaritalStatus = false; // Boolean

let myPets = ["Dog", "Rabbit", true, 12]; // Array

let myself = {
  'name': 'Matthew',
  'age': 27,
  'married': false
  'hobbies': ['Coding', 'More Coding', 'Coding Again']
} // JSON / Object

```

## 3. Outputs

``` JAVASCRIPT

document.write('<h1>Hello World</h1>')
console.log('Hello World')
alert('Hello World')

```

## 4. Functions

``` JAVASCRIPT

// Functions

// Simple function without an argument or parameter

function sayHello(){
    alert("Hello!");
  };

  sayHello();

// Function that requires arguments or parameters to be passed in

  function introduceMyself(name, age, maritalStatus, pets){
      document.write("<h1>About Me!</h1>");
      document.write(`<h3>My Name is: ${name} </h3>`)
      document.write("<h3>My Name is: " + name + "</h3>");
      document.write("<h3>My Age is: " + age + "</h3>");
      document.write("<h3>Am I married? " + maritalStatus + "</h3>");
      document.write("<h3>My Favorite Pet is my: " + pets[1] + " " + pets[0] + "</h3>");
    };

  introduceMyself(myName, myAge, myMaritalStatus, myPets);

```