Javascript OO

[E]very JavaScript method has an implicit "this" parameter that represents the object through which the method was invoked. "this.x" will reference the x property of point1, because we invoke the add method using point1...

When we use the new operator with the Point function, the new operator will first create a new object. The new operator then invokes the Point function and passes a reference to the newly created object in the implicit "this" parameter.

...all objects created by a constructor function will have the same prototype

..so the prototype approach is more efficient (shared function objects)

A closure in JavaScript is an inner function that references a local var or parameter in its outer function. Those local variables and parameters, which typically go out of scope when the outer function finishes execution are now "enclosed" by the inner function, which can continue to reference and use those variables.

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