.bash_profile VS. /etc/profile

The global /etc/profile and your own local ~/.bash_profile are read when the shell is invoked as an interactive login shell, for example when you open a remote terminal session to someone else's machine, or when you log into your own machine without X Windows running, or when you hit ctrl-alt-F1 from X Windows to start a virtual terminal session.

The global /etc/bashrc (if it exists) and your own local ~/.bashrc is read when the shell is invoked as an interactive non-login shell, for example when you open up a terminal window in Gnome or KDE.

So you will be wanting modify /etc/bashrc if you want to the setting for all users, or in your ~/.bashrc if it's just for you.

Source: http://www.experts-exchange.com/Operating_Systems/Linux/Q_20895782.html