hasownproperty in html code example

Example 1: javascript hasownproperty

var person = {	
  	"first_name": "Bob",
	"last_name": "Dylan"
};
person.hasOwnProperty('first_name'); //returns true
person.hasOwnProperty('age'); //returns false

Example 2: has own propriety javascrip

var x = {
    y: 10
};
console.log(x.hasOwnProperty("y")); //true
console.log(x.hasOwnProperty("z")); //false