title: What, exactly, does ssh-copy-id do?
body: <p>What does the ssh-copy-id command do, exactly?  I've used it numerous times and it works great.  However, when I try to manually cut and paste my .pub keyfile to my remote authorized_keys, it doesn't work.</p>
  
  <p>I've compared the contents of my authorized_keys file where I've cut and pasted the .pub into it vs subsequently using ssh-copy-id and I'm not seeing any differences between the two, including whitespace.</p>
  
  <p>Is there anything that ssh-copy-id does beyond copying the public key into authorized_keys?</p>