Ripping is the process of copying data from a CD or DVD to a hard disk. This is done using a software utility, often referred to as a CD or DVD "ripper," which can extract audio or video data from optical media.
While "ripping" sounds destructive, the process does not affect original data. However, the copied data may be modified during the ripping process so that it can be played on a computer. For example, DVD ripping programs may convert .VOB video files (which are formatted for DVD players) to standard .MPG files. The resulting video data can be played back using a basic video player program.
Once data has been ripped from a disc, it can be played back without requiring the original disc to be present. Therefore, ripping is useful for archiving media on your computer or for backing up audio and video data. However, most commercial CDs and DVDs are copyrighted, meaning you are not allowed to copy the data to other discs or redistribute the data from your computer. Also, it is typically a violation of copyright to rip data from a disc that you do not own. Therefore, make sure you know are familiar with the usage policy of the media before you rip it to your hard disk.