Correct permissions of files and folders Apache Ubuntu (Linux)

To change the permissions of files only:

find . -type f -exec chmod 0644 {} \; 

To change the permissions of folders/directories only:

find . -type d -exec chmod 0755 {} \; 

Note that 644 is the correct permission of files on a Webserver (Apache) and 755 is the correct permission for folders. PHP files should have permissions of 600.