Const and Let Keywords w ES6
function f() {
var x = 1
let y = 2
const z = 3
{
var x = 100
let y = 200
const z = 300
console.log('x in block scope is', x)
console.log('y in block scope is', y)
console.log('z in block scope is', z)
}
console.log('x outside of block scope is', x)
console.log('y outside of block scope is', y)
console.log('z outside of block scope is', z)
}
f()
Outrageous Ostrich