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copied!<p>"Heap" and "stack" are outmoded, inaccurate and confusing terms relating to storage duration.</p> <p>Objects with "automatic storage duration" are what silly people call "stack objects". They're the ones that you will define inside a function as "local variables". They go out of scope when their enclosing block ends.</p> <p>Objects with "dynamic storage duration" are those that you create on the <em>free store</em> with the aid of the keyword <code>new</code> (or, if you're silly, <code>malloc</code>), and then destroy whenever you like with the keyword <code>delete</code> (or, if you're silly, <code>free</code>).</p> <p>There are also objects with "static storage duration" that are subject to all sorts of bizarre rules of initialisation order and things. We tend not to use them in idiomatic C++ as much as we can help it.</p> <p>As for the specific variables in your code example, your comments are all accurate, despite the failure in terminology.</p> <p><strong>Addendum:</strong></p> <p>The terms "heap" and "stack" are outdated, relating to back when the most popular runtime libraries used these data structures to store objects which were dynamically- and automatically-allocated, respectively (statically-allocated objects fit into neither category, incidentally).</p> <p>These days that is not always true, and it's certainly not mandated by the C++ standard, which does not care where things are stored. It only cares about how they are created and destroyed, and about how long they live.</p>

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