the images or music of a dvd are divided into some units, among which title is the biggest one. to an image in video software, title is movie, to a piece of music in audio software, it is music.
chapter
it is smaller than title among the units of a dvd. a title is made up of several chapters, and each chapter has a number for search.
but some discs may not have numbered chapters.
track
the music in a cd. each track has a number for search.
structure of dvd
