how did sudo command solved can't open device "/dev/ttyUSB0": Permission denied?

[arunksoman]

1. Go to Arduino software
2. Download Linnux 64-bit or 32-bit software
3. Extract the Downloaded tar.xz file on your home directory.
4. Navigate to your extracted file using cd command:
   cd arduino-1.8.12-linux64
5. Make the install.sh file executable:
   sudo chmod +x install.sh
6. Install arduino using shell script
   sudo ./install.sh
7. Open Terminal and type:
   ls -l /dev/ttyACM*
   you will get something like:
   crw-rw---- 1 root dialout 188, 0 5 apr 23.01 ttyACM0
   The "0" at the end of ACM might be a different number, or multiple entries might be returned. The data we need is "dialout" (is the group owner of the file).
   Now we just need to add our user to the group:
   sudo usermod -a -G dialout <username>

I believes it is a better way to solve your problem. Other way you to try to solve problem is install arduino via:
sudo apt-get install arduino-core

[Abhay]

@arunksoman thanks for the steps
but the thing is I don't have issues with port now, I was curious how it got resolved without going through the usual steps but by using sudo command.

[arunksoman]

@Abhay What did you mean by usual steps?

[Abhay]

@arunksoman by usual steps I meant adding our user to the group.
ie the step
sudo usermod -a -G dialout <username>

[arunksoman]

@Abhay I think most probably you might have done this earlier while installing Arduino.

[Abhay]

@arunksoman thanks,
I will look more into it. Thanks again