Linux and Apache

Avoid locking your web-uploaded files

Out of the box, most webservers will run Apache processes as user 'www-data', which has it's own group. If you then try to move/delete/edit any files created by this user via FTP or SSH, you are likely to be denied access. This often happens when files are uploaded with a CMS. Login via SSH as root and drop in this command which will add your user to the www-data group. This will allow your user to edit files that are shared within the www-data group. Win!

sudo usermod -a -G www-data [yourusernamehere]