Make shortcuts to directories via terminal
I keep aliases in ~/.bash_profile.

Terminal and iTerm 2 open new shells as login shells by default. When bash is invoked as an interactive login shell, it reads ~/.bash_profile but not ~/.bashrc. The terminal emulators on other platforms often open new shells as non-login shells, so for example bash reads ~/.bashrc but not ~/.bash_profile. OS X users often use ~/.bash_profile as the personal configuration file corresponding to ~/.bashrc on other platforms, but it is also possible to source ~/.bashrc from ~/.bash_profile or to tell Terminal or iTerm 2 to open new shells as non-login shells.

If both ~/.profile and ~/.bash_profile exist, bash only reads ~/.bash_profile when it is invoked as an interactive login shell. ~/.profile is also used by other shells and programs that might not understand the same configuration options as bash.

/etc/bashrc is owned by root, and it might get replaced when you upgrade OS X.

See man bash|less +^INVOCATION or https://www.gnu.org/software/bash/manual/html_node/Bash-Startup-Files.html for more information.