Take the 2-minute tour ×  I downloaded google-chrome for Linux,
it got downloaded as a .deb file in downloads folder. I changed
the current directory to the downloads folder and ran "google-
chrome" in terminal. It started google chrome, but the issue is
that .deb file is not a script(as I understand). Then how did
the terminal understand that the 'google-chrome' command meant
to start it? Commands like emacs...etc are already built-in.
What about this command which is new to bash? How did it
recognise it?  share|improve this question One of the answers
starts with "You probably already had google-chrome installed on
your computer." Otherwise, there's no way that running google-
chrome from a terminal would do what you feel it did. – 
user25656 Apr 18 '13 at 11:14 add comment  3 Answers  up vote 7
down vote accepted  First a few basics:  When you run a command
on your terminal, you enter the name of a file, (which should be
executable): if you enter a simple name e.g. emacs, the system
searches a number of dire