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    <p>You can cause a stack overflow quite easily in python, as in any other language, by building an infinately recursive funcion. This is easier in python as it doesn't actually have to do anything at all other than be recursive.</p> <pre><code>&gt;&gt;&gt; def foo(): ... return foo() ... &gt;&gt;&gt; foo() Traceback (most recent call last): File "&lt;stdin&gt;", line 1, in &lt;module&gt; ....... File "&lt;stdin&gt;", line 2, in foo RuntimeError: maximum recursion depth exceeded &gt;&gt;&gt; </code></pre> <p>As for the heap, that is managed by a garbage collector. You can allocate lots of objects and eventually run out of heap space and Python will raise a <code>MemoryError</code>, but it's going to take a fair amount of time. You actually did that with your 'stack overflow' example in the question. You stored a reference to a string on the stack, this string took up all the free memory available to the process. As a rule of thumb, Python stores a reference to a heap structure on the stack for any value that it can't guarantee the size of. </p> <p>As for how it all works, from the fist example you can see that python has a built-in limit to the depth of the call stack that it will not exceed. The amount of memory available for heap space is defined by the OS however and will depend upon many factors. </p> <p>These are should be the appropriate parts of the python docs for infomation on the errors themselves:</p> <ul> <li><a href="http://docs.python.org/release/3.2.3/library/exceptions.html#RuntimeError">http://docs.python.org/release/3.2.3/library/exceptions.html#RuntimeError</a></li> <li><a href="http://docs.python.org/release/3.2.3/library/exceptions.html#MemoryError">http://docs.python.org/release/3.2.3/library/exceptions.html#MemoryError</a></li> </ul>
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    1. POHow to cause stack overflow and heap overflow in python
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    1. COSo if we create a large string it is also stored in the heap as well? I thought strigns were stored in stack and thats one reason for being immutable. I ve seen that in the python visualizer where if u create strings they are placed in frames which implies stack. hmmm
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    2. COYes and no, although python strings are immutable sequences there is no specific way in which they must be stored. You can't store them in the stack frame and must store them as a reference however otherwise you wouldn't be able to return a string from a method as it's data would go out of scope when the function returned. (This is a simplification. There are lots of ways to implement a Python intepreter).
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    3. COI think this is a confusing grey area between how the string type is implemented and how the python interpreter presents it to the program.
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