Comments 
// Comment

/* Multi-line Comment */

Comments are ignored in code.

Introduction JS
script 
<script src="" defer></script>

Attributes:
defer // waits until DOM is fully loaded
async // doesn't rely on other scripts, doesn't matter when script is executed

Used to add Javascript to HTML files.

Introduction JS
Variables 
let _$variableName1 = Data;
const Immutable = Data;

Use let if data should change, const if not. Can use $, underscore, or digits, can't start with a digit, camelCase. Use = to give a variable data. Don't use var.

Introduction JS
Statements 
;   // semi-colons seperate statements
    // Javascript ignores whitespace 
{}  // Codeblocks are contained, to group statements

function(){}; // JS requires keywords to start actions

Statements are used to write javascript code.

Introduction JS
Data Types 
1. String    // Includes characters, whitespace, symbols, surrounded by quotes 
2. Number    // Numbers that arithmetic value
3. Bigint    // Store larger integer values
4. Boolean   // True or False Values (On | Off)
5. Undefined // Value not assigned
6. Null      // Reference to a non-existing object
7. Symbol    // Create unique identifiers for objects
8. Object    // Could be an object, array, date

All the different types of data used in javascript.

Introduction JS
Truthy | Falsy 
false, 0, ' ', null, undefined, NaN

Above are falsy values, everything else is truthy.

Introduction JS