The Bourne Again Shell (located in /bin/bash) is the default shell of the Linux operating system and is the shell that users of that system will likely be most familiar with.
One of bash's strongest features, shared with the Bourne shell, is flexible output redirection.
Note: Bash is not available by default in the base system, but can easily be installed from ports if desired.
See bash's man page for more info.
see also: bash homepage
To change your shell from one to another, run the chsh command.
To change bash's look and feel, edit your shell configuration file -- .profile and/or .bashrc (may be called .bash_profile on older systems).
Other shells that you can install and customize for ease of use are the bash, tcsh, psh, ksh, zsh.
See also Changing_your_shell and Gotchas, Linux