Example of this in Js

app.js

 var fn = function (a,b){
  console.log(this , a , b);
             
 }
 
 var red = { method : fn };

 red.method(1,2); // { method : fn }, 1,2

 fn(1,2) // window, 1,2

 fn.call(red, 1,2) // { method : fn }, 1,2

  var yellow = "yellow";

 red.method.call(yellow, 1,2); // yellow, 1,2