And as you are asking about "system wide":
Configuration files located in the
/etc directory apply to all users on the system. For
/etc/bash.bashrc this would mean to all and everything that's using the "Borne Again SHell" aka Bash on that machine. Even if you're the only human using it, there could be "technical users" affected (simply take a look into the
/etc/passwd and check how often the term "/bin/bash" is stated there -- or use
grep bash /etc/passwd | wc -l, which should give you that number directly (meaning: "grab" all lines containing the string "bash" from the file "/etc/passwd", and send the results ("|") to the command "wc" (word count) to count the lines ("-l").
So for your user, it is much safer to modify
~/.bashrc instead (meaning the file ".bashrc" -- with a leading dot, yes -- in your home-directory, e.g.
/home/ankur/.bashrc), which then just affects your user and leaves everything else alone. Files in
/etc should only be changed if system-wide changes are really intended.
Besides: Both configurations will be used if they exist. First, the system-wide file (here:
/etc/bash.bashrc) is read and "sourced" (it's settings applied to the current session), and then the users
/home/username/.bashrc is handled the same, and thus can add to or even change/overwrite settings from the global