You can do that simply from your admin backend with out downloading any files etc.,.
So login to the backend go to extensions, click on ‘templates manager’, in the next screen choose the template which is being used for the website and go to the closing just before that, place this tag there:
setGenerator(‘Enlightened Generator’); ?>
You can leave the tag empty OR enter your own words! The title tag can be changed from the menu item, and the description tag from the article page or module.
Don’t use the global setting to add the tags, it will apply it to all the pages, so that is not good, go by article by article that is best. Google doesn’t like title tag duplication.
Get in touch with out search engine experts to know how else you can optimize your joomla website for better ROI and customer traffic!