How can telnet connect to an arbitrary port?
<p>Through <code>telnet</code> I am able to connect to any server at any port, how does it work? Is there a telnet server daemon running on that server?
If there is, shouldn't the daemon listen on a specific port? why can I connect to an arbitrary port on that server? 
Why can I telnet to <code>127.0.0.1</code> at <code>80</code> port and get a response from my Nginx without a telnet daemon running on my Ubuntu?</p>