var vs let vs const

gistfile1.txt

var, let, and const. What are the differences of the three and which ones should you use?

If you do not know what let and const are, they are basically different variations of the “variable”, derived from ES6.

Variables are absolutely essential to any programming language, but in Javascript, the var keyword does has some flaws. 
Thats where ES6 variables come in.

When you declare a const = Cannot be updated
When you declare a let = The variable can only be used in the block its created in

What do I mean by “block”? 
Anything inside a pair of curly braces is a block.

Now lets take a look at some examples to better understand var let and const

// const

const yo = ‘Hello’;
yo = ‘Hey’;


// console: **ERROR**

// let

function greetings(){
    if (true) {
        let greeting = ‘whats up’;
    }
console.log(greeting);
}

// console: **ERROR**