Starting with Joomla 1.5 and its move to Internationalization and full support of UTF-8, messages for footer.php and other Joomla pages has been moved to a language specific file.
As before if you want to change the text, go to the language directory, go to the folder of the language you want to change, find the mod_footer.ini file and change the relevant text. For British English, the specific file is language/en-GB/en-GB.mod_footer.ini. Remember that you may not remove copyright and license information from the source code. However note that this means that every time you update Joomla the language file will be overwritten with the old copyright.
A better solution is to create a language string override in the language. See the Joomla 2.5 or Joomla 3.1 help screens for more information on how to do this
If you want to remove the footer entirely, go to Extensions > Module Manager and unpublish the footer module.
Other places where can look for options to make changes are these. If you find code related to footers in these files, you can either "comment it out" or remove it:
- /includes/footer.php file.
- index.php file for your active template
