www and public_html There is no difference between the two. The actual directory that you place your web files in is public_html, but www is a symbolic link
More...How to clear the uninstalled files and folders in Public_html folder?Follow the below steps to uninstall the files in public_html folder.Step
More...Can you delete the files in public_html folder? Deleting files from public_html folder will completely erase the specified file content from the website.
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