bash - Launches the Bourne-Again SHell, an sh-compatible shell that incorporates useful features from the Korn and C shells (ksh and csh).
Syntax bash [options] Options -c string Commands are read from string. If there are arguments after the string, they are assigned to the positional parameters, starting with $0. -D A list of all double-quoted strings preceded by $ is printed to standard output. These are the strings that are subject to language translation when the current locale is not C or POSIX. This implies the -n option; no commands will be executed. -PO- = output in the GNU gettext (portable object) file format. -i Interactive shell. -l Make bash act as if it had been invoked as a login shell. -r RESTRICTED SHELL -s If the -s option is present, or if no arguments remain after option processing, then commands are read from the standard input. This option allows the positional parameters to be set when invoking an interactive shell. -v Verbose output. -- A -- signals the end of options and disables further option processing. Any arguments after the -- are treated as file- names and arguments. An argument of - is equivalent to --.
bash is the default in OS X Panther 10.3, Tiger 10.4 and Leopard 10.5
To Exit bash type exit
Your default shell can be accessed from System Preferences > Accounts, Right click (or control-click) on an account and choose Advanced Options.
You can also set a default shell for the terminal:
Open the Terminal app (Applications > Utilities > Terminal) then open Terminal Preferences
Whatever the default, you can always switch shells on the fly by just typing the name of new shell - bash, csh, tcsh or zsh.
“What distinguishes the majority of men from the few is their inability to act according to their beliefs” ~ Henry Miller