Lets say your server has a file structure like this:
Code:
/home/your_account_name/public_html/phpbb2/images/an_image.png
(ABSOLUTE) phpbb2 root path = /home/your_account_name/public_html/phpbb2/
If you want to access files RELATIVE to that root path, they can be srced directly such as <img src=images/an_image.png>. It just means, if you want to src an image file, you only need to provide the part of the file location that is after the phpbb2/ folder.
An alternative file structure: What if you have the images folder outside of the phpbb2 folder?
Code:
/home/your_account_name/public_html/phpbb2/
/home/your_account_name/public_html/images/
to access the images folder from the phpbb2 root folder you need to specify the file source like this:
src="../images/an_image.png" - the ".." means go up one folder.
Hope this helps.