Question

Javascript functions can be declared on a objects prototype like this:

<object name>.prototype.<variable name>=function(){
//
//
}

How it this different than following declaration?

<object name>.<variable name>=function(){
//
//
}

How are prototype functions different than normal functions in javascript ?

Answer 1

functions declared on a base object’s prototype are inherited by all instances of that object type.

For example..

String.prototype.foo = function () {
  return 'bar';
};

Now, every string will have the function foo() available.

'test'.foo(); // returns 'bar'

Read more about prototype-based inheritance here