Fire and release a process

There are some small little tricks that are very useful but not well known by most people. Just in case someone needs it, one of these follows:

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<blockquote>On *nix systems it is possible to fire a process from the terminal window and release the terminal for other tasks. This is handy when starting X processes or any other process that could run well on the background (like updating the locate db for instance).

I knew it was possible but could not remember how to do it until I accidentally laid my eyes on an example. So here is the code to start emacs (Xemacs) and release the terminal: