MakeMKV is a program that allows you to make copies of your DVDs to your hard disk. If you have a DVD disc with a movie (for example your movie from wedding) and you don’t have it on your hard drive, you can use a ripper program like this to copy the content (video) from disc to local computer and then use it as you want (play it directly from PC, burn it to another DVD, copy to another hard drive and so on).
It can read DVD and Blurays, preserves all data (audio, subtitles etc.) from source disc and you will have final file saved to your desktop with the same quality as input source.
Version for Linux is available on developer’s forum.