how to use or in javascript code example

Example 1: or in js

// The Or operator in Javascript is 2 vertical lines = ||

//Example
var firstnumber = 10;
var secondnumber = 20;

//The Or operator in action
if(firstnumber > 20 || secondnumber< 10) {
}

Example 2: javascript if or

let A = 1;
let B = 0;
if (A == 1 || B == 1){
  	// some code here
}

Example 3: and operator in javascript

//&& returns true if both values are true
//or returns the second argument if the first is true
var a = true
var b = ""
var c = 1

true && "" //""
"" && 1 //""
false && 5 //false