How it works? I got some code running in an IPython Notebook. Some iterative work.

Accidentally I closed the browser with the running Notebook, but going back to the IPython Dashboard I see that this particular Notebook hasn't Shutdown, so if I open the Notebook again I see the [*] in front of my code that it was executing.

I even can hear my PC still running the code, but it doesn't return me any new output of the print statements.

Can I wait and eventually continue with the output, or my PC will still running my code, but it won't be accessible anymore?

When you start up ipython, it is essentially creating a web server that is running on a separate process. The code itself is running on the web server, or kernel. The web browser is simply one of several front-ends that can view and edit the code on the kernel.

This design allows ipython to separate the evaluation of code from the viewing and editing of code -- for example, I could access the same kernel via the web interface (ipython notebook), the console (ipython console), or the qt console interface (ipython qtconsole).

Your PC will continue to run the code, though I believe that the output requested by one frontend will not show on any other frontends using the same kernel (I'm not 100% certain about this though).

You can find more information here.