user.js

function User1( name, age ){
  this.name = name;
  this.age = age;
}
// Add a new function to the object prototype
User1.prototype.getName = function(){
  return this.name;
};
User1.prototype.getAge = function(){
  return this.age;
};
var bob = new User1( "Bob", 44 );
console.log("User1: " + bob.getName() + ", Age: " + bob.getAge());
for (var p1 in bob) {
  if (bob.hasOwnProperty(p1)) {
    console.log(p1);
  }
}
// User1: Bob, Age: 44
// name
// age


function User2 (name, age ) {
  this.name = name;
  this.age = age;
  this.getName = function() {
    return this.name;
  };
  this.getAge = function() {
    return this.age;
  };
}
var bill = new User2( "Bill", 44 );
console.log("User2: " + bill.getName() + ", Age: " + bill.getAge());
for (var p2 in bill) {
  if (bill.hasOwnProperty(p2)) {
    console.log(p2);
  }
}
// User2: Bill, Age: 44
// name
// age
// getName
// getAge