I had an executable script on my ubuntu located on ~/project/ directory and I tried to add that path to /etc/environment . So , I edit the path to this PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:~/project/" . Then , I logout and login back , open the terminal as su and run the command to execute my script on that folder but the result is command not found. Then, I change the path in /etc/environment to PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/r0xx4nne/project/" and voila it works.Now i can run the executable script inside ~/project/ without fail under su command. My question is , what's the difference between ~/project and /home/r0xx4nne/project when it comes in case of creating a path in /etc/environment ? Why it happened to be like this? I am a newbie and I just want to know more . Thanks for any reply .