Change the default shell started at login.
chsh [-s shell] [username]
-s shell specifies the name of the shell executable to use (shell can be any program listed in the /etc/shells file, such as /bin/bash and /bin/csh).
A user's default shell is stored in the /etc/passwd file. The chsh command lets you change the default shell to any of the shells listed in the /etc/shells file. If you type chsh without any arguments, chsh prompts you for the name of a shell.