What is the difference between bin/sh, bin/bash, sbin/nologin, bin/tcsh, etc?
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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. 

 1. What is the difference between these options? 
 2. Which option should I choose?

Access to the server over SSH:

 - /bin/sh 
 - /bin/bash 
 - /sbin/nologin 
 - /bin/tcsh 
 - /bin/csh 
 - /bin/ksh 
 - /bin/bash (chrooted) 
 - /bin/rbash

Here is an image of the Plesk control panel:

![enter image description here][1]


  [1]: http://i.stack.imgur.com/qGt45.png