That's Bill Marsh's site, which I remember him discussing at ePo. Maybe that's how your performance ended up there. ;)

b

Note the new asterisks whenever we reference favoriteNumber, except for that new line right before the return.

When a variable is finished with it's work, it does not go into retirement, and it is never mentioned again. Variables simply cease to exist, and the thirty-two bits of data that they held is released, so that some other variable may later use them.

That gives us a pretty good starting point to understand a lot more about variables, and that's what we'll be examining next lesson. Those new variable types I promised last lesson will finally make an appearance, and we'll examine a few concepts that we'll use to organize our data into more meaningful structures, a sort of precursor to the objects that Cocoa works with. And we'll delve a little bit more into the fun things we can do by looking at those ever-present bits in a few new ways.

This is another function provided for dealing with the heap. After you've created some space in the Heap, it's yours until you let go of it. When your program is done using it, you have to explicitly tell the computer that you don't need it anymore or the computer will save it for your future use (or until your program quits, when it knows you won't be needing the memory anymore). The call to simply tells the computer that you had this space, but you're done and the memory can be freed for use by something else later on.

We can see an example of this in our code we've written so far. In each function's block, we declare variables that hold our data. When each function ends, the variables within are disposed of, and the space they were using is given back to the computer to use. The variables live in the blocks of conditionals and loops we write, but they don't cascade into functions we call, because those aren't sub-blocks, but different sections of code entirely. Every variable we've written has a well-defined lifetime of one function.