'Dvd identifier' retrieves and interprets the pre-recorded information that is present on dvd (dvd+r, dvd+rw, dvd-r, dvd-rw, dvd-ram), hd dvd (hd dvd-r, hd dvd-rw, hd dvd-ram) and blu-ray (bd-r, bd-re). This information contains a variety of parameters such as disc manufacturing information and supported write speeds. Even though some of this information is usually printed on the packaging.