I am new to the whole Apple scene as I will be switching from a PC to a Macbook Pro in a couple months. I happen to see that Apple releases a lot of updates to their Macbooks. It looks like to me that most of these "updates" can be done by downloading without having to purchase anything. I guess my question would be how do you know if your Macbook is all up-to-date on updates? Does something come up on the screen that prompts you to update or is their a certain website that you need to go to? Thanks