This back and forth is an important concept to understand in C programming, especially on the Mac's RISC architecture. Almost every variable you work with can be represented in 32 bits of memory: thirty-two 1s and 0s define the data that a simple variable can hold. There are exceptions, like on the new 64-bit G5s and in the 128-bit world of AltiVec

This code should compile and run just fine, and you should see no changes in how the program works. So why did we do all of that?

Let's take a moment to reexamine that. What we've done here is create two variables. The first variable is in the Heap, and we're storing data in it. That's the obvious one. But the second variable is a pointer to the first one, and it exists on the Stack. This variable is the one that's really called favoriteNumber, and it's the one we're working with. It is important to remember that there are now two parts to our simple variable, one of which exists in each world. This kind of division is common is C, but omnipresent in Cocoa. When you start making objects, Cocoa makes them all in the Heap because the Stack isn't big enough to hold them. In Cocoa, you deal with objects through pointers everywhere and are actually forbidden from dealing with them directly.

A variable leads a simple life, full of activity but quite short (measured in nanoseconds, usually). It all begins when the program finds a variable declaration, and a variable is born into the world of the executing program. There are two possible places where the variable might live, but we will venture into that a little later.

To address this issue, we turn to the second place to put variables, which is called the Heap. If you think of the Stack as a high-rise apartment building somewhere, variables as tenets and each level building atop the one before it, then the Heap is the suburban sprawl, every citizen finding a space for herself, each lot a different size and locations that can't be readily predictable. For all the simplicity offered by the Stack, the Heap seems positively chaotic, but the reality is that each just obeys its own rules.

2000, etc.) in 29 brief, lyrical "tangos" celebrex (which are kind of like stanzas, only a lot ambien more romantic) that have little quotations from soma Keats in front of each. Basically, it's Girl-meets-Boy, phentermine Girl-gets-Boy, Girl-and-Boy-grow-old-and-get-tired-of-each-other. paxil A marriage, in other words. Narrated mostly phentermine by the wife, it becomes quickly lugubrious in didrex a sort of Liv Ullmann/Sylvia Plath-ish kind cialis of way ("I believe / your taxi is here she said. didrex / He looked down at the street. She was right. tramadol It stung him, / the pathos of her keen hearing"), propecia