EcmaScript 6 Startup tutorials

LET Keyword

The let keyword declares a local variable in the block scope. Normally ifstatements don’t have scope, but now they do with let.

This also works for loops too.

for Example : 

var x = 1;
	if(x < 10) {
	let v = 1;
	v = v + 21;
	console.log(v);
	}
	console.log(v); //v is not defined

CONST keyword

A const or a constant declaration is where once, the variable is set you can’t change it. It’s read-only.

For example : 

  const admin = "jain";

   admin = "pardeep" //not allowed...readonly