How to know Internet usage of any process in Ubuntu/Mint/Debian?

To know,which process is using your internet in your system hiddenly then you have to follow below steps.

1.Install nethogs tool by putting this command into terminal.

    sudo apt-get install nethogs

2.Then you have to use it.

put this commands to check internet usage of the processes.

                   sudo nethogs [connection_type]

[connection_type]=ppp0 for mobile internet,eth0 for broadband/ethernet,wlan0 for wifi internet

example: sudo nethogs ppp0

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