define value in js

//choose the best for your solution
var myVariable = 22; //this can be a string or number. var is globally defined

let myVariable = 22; //this can be a string or number. let is block scoped

const myVariable = 22; //this can be a string or number. const is block scoped andvar var1 = 1; //value
var var2 = "str";
var var3 = 'char';var /*var*/ = /*What it does*/