problem uploading code

avrdude: Version 6.3-20171130
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

System wide configuration file is "/opt/arduino-1.8.9-linux64/arduino-1.8.9/hardware/tools/avr/etc/avrdude.conf"
User configuration file is "/home/jairam/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/ttyUSB0
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: ser_open(): can't open device "/dev/ttyUSB0": Permission denied

avrdude done. Thank you.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
hello everyone. i am having these problems when i am trying to upload sketches into my arduino nano.. does someone know how to fix this..
i use ubuntu 18.04 lts
thanks in advance..
Arduino: 1.8.9 (Linux), Board: "Arduino Nano, ATmega328P"

Sketch uses 930 bytes (3%) of program storage space. Maximum is 30720 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can't open device "/dev/ttyUSB0": Permission denied
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

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