Always remove your metadata from your images before you upload them; see here.
With this script one can remove only some of the metadata. Important information like ISO-Speed, Aperture time etc. will not be removed. These may contain interesting information for other people. Information about the author will be added.
This script works on the original files you choose, so be sure to work only on copies. If you choose a .CR2 or .cr2 file you get an error message, because manpage of exiftool says you shouldn't remove metadate from those files.