js.l2 code example

Example 1: js.l2

// Lightweight = does not use computer memory.
// cross-platform = can not use multiple platform.
// object oriented = based on object.
// client-site = run on the own browser.
// server-side = use multiple server facilities. like => node.js , jquery , angular.

Example 2: js.l3

main:
// var x; => older & bolkey & re-definable.
// let y; => mordern & re-definable.
// const z; => mordern & do not re-definable.


Example:
var x = 50+10;
console.log(x);
x = 'dulon';
console.log(x);

let y = 60+10;
console.log(y);
y = 'mahadi';
console.log(y);

const z = 100+20;
console.log(z);
z = ('mahadi');
console.log(z);  // print error massage [ does not change const value / re-define ]