title: What is the difference between bin/sh, bin/bash, sbin/nologin, bin/tcsh, etc?
body: <p>I am new to linux so please go easy and talk slow =) </p>
  
  <p>In Plesk I have some options for accessing the server over SSH. I just want to connect, add my public key and run rsync for backup. </p>
  
  <ol>
  <li>What is the difference between these options? </li>
  <li>Which option should I choose?</li>
  <li>What are these? They look like directories to me.</li>
  </ol>
  
  <p>Access to the server over SSH:</p>
  
  <ul>
  <li>/bin/sh </li>
  <li>/bin/bash </li>
  <li>/sbin/nologin </li>
  <li>/bin/tcsh </li>
  <li>/bin/csh </li>
  <li>/bin/ksh </li>
  <li>/bin/bash (chrooted) </li>
  <li>/bin/rbash</li>
  </ul>
  
  <p>Here is an image of the Plesk control panel:</p>
  
  <p><img src="https://i.stack.imgur.com/qGt45.png" alt="enter image description here"></p>