Dvd9 dvd5 dvdrip

Sorry for my bad question, but what is all of theese.What is dvd9 for and dvd5. And what is dvd rip and MKV?
Answer #1
DVD9 refers to a double layer DVD (8.5GB).
DVD5 refers to a singler layer DVD (4.7GB).
DVDRip refers to a movie ripped from a DVD.
MKV is a container for a video file, most often used for HD movies.
Answer #2
thank u for clear expression