Nerd alert!) When a daemon program is started, it fires up a
second child process, detaches it, and then the parent process
dies. This is called forking. Because the parent process dies,
it will give the console back and it will look like nothing has
happened. But wait: the child process is still running. Even if
you close your terminal, the child continues to run in memory,
until it either stops, crashes or is killed. In PHP: forking can
be achieved by using the Process Control Extensions. Getting a
good grip on it, may take some studying though.