Ubuntu operating system(OS) gives more importance to security. So all types operations need root permissions. Two ways give permissions in Ubuntu. To do this, you need root access.
one ways is to right click on on file/folder and edit permissions.
The second way is through terminal(CMD).
command:
sudo chmod 777 pathtofile/folder
Eg : sudo chmod -R 777 /var/www/smarttips/
sudo chmod -R 777 /var/www/smarttips/index.php