File: //usr/share/webmin/useradmin/help/shell.html
<header>Shell</header>
When a user logs in via telnet or at the console, or opens an <tt>xterm</tt>
window in X the users shell program will be run to interpret commands
entered. If a user does not have a valid shell program or has one that
does nothing (like <tt>/bin/false</tt>), then that user will not be able to
login. This can be useful when creating users who can only read and send
email. <p>
Listed in this field are all the shells used by users on your system. You
may select one, or choose <i>Other..</i> and enter the full path of the
shell in the text field below. <p>
All Unix systems come with the Bourne shell (<tt>/bin/sh</tt>) and the
C Shell (<tt>/bin/csh</tt>). Other common and more user-friendly shells
are <tt>tcsh</tt>, <tt>zsh</tt> and <tt>bash</tt>.
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