Ripping is the extraction of digital content from a container, such as a CD, onto a new digital form and location. Later, the term was applied to ripping WAV or MP3 files from digital audio CDs, and after that to the extraction of contents from any storage media, including DVD and Blu-ray discs, as well as the extraction of video game sprites.
Ripping is often used to shift formats, and to edit, duplicate or back up media content. A rip is the extracted content, in its destination format, along with accompanying files, such as a cue sheet or log file from the ripping software.
To rip the contents out of a container is different than simply copying the whole container or a file. When creating a copy, nothing looks into the transferred file, nor checks if there is any encryption or not, and raw copy is also not aware of any file format. One can copy a DVD byte by byte via programs like the Linux dd command onto a hard disk, and play the resulting ISO file just as one would play the original DVD.
To rip contents is also different than grabbing an analog signal and re-encoding it, as it was done with early day CD-ROM drives not capable of digital audio extraction (DAE). Sometimes even encoding, i.e. digitizing audio and video originally stored on analog formats, such as vinyl records, is incorrectly referred to as ripping.
Software
A CD ripper is a piece of software designed to extract or "rip" raw digital audio (in format commonly called CDDA) from a compact disc to a file or other output. Some all-in-one ripping programs can simplify the entire process by ripping and burning the audio to disc in one step, possibly re-encoding the audio on-the-fly in the process.
For example, audio CDs contain 16-bit, 44.1 kHz LPCM-encoded audio samples interleaved with secondary data streams and synchronization and error correction info. The ripping software tells the CD drive's firmware to read this data and parse out just the LPCM samples. The software then dumps them into a WAV or AIFF file, or feeds them to another codec to produce, for example, a FLAC or MP3 file. Depending on the capabilities of the ripping software, ripping may be done on a track-by-track basis, or all tracks at once, or over a custom range. The ripping software may also have facilities for detecting and correcting errors during or after the rip, as the process is not always reliable, especially when the CD or the drive containing the CD itself is damaged or defective.
There are also DVD rippers which operate in a similar fashion. Unlike audio CDs, DVDs do contain data formatted in files for use in computers. However, commercial DVDs are often encrypted (for example, using Content Scramble System/ARccOS protection), preventing access to the files without using the ripping software's decryption ability, which may not be legal to distribute or use. DVD files are often larger than is convenient to distribute or copy to CD-R or ordinary (not dual-layer) DVD-R, so DVD ripping software usually offers the ability to re-encode the content, with some quality loss, so it fits in smaller files.
Legality
When the material being ripped is not in the public domain, and the person making the rip does not have the copyright owner's permission, then such ripping may be regarded as copyright infringement. However, some countries either explicitly allow it in certain circumstances, or at least do not forbid it. Some countries also have fair use-type laws which allow unauthorized copies to be made under certain conditions.
Europe
A directive of the European Union allows its member nations to instate in their legal framework a private copy exception to the authors and editors rights. If a member State chooses to do so, it must also introduce a compensation for the copyright holders. Most European countries, except for Norway, have introduced a private copying levy that compensates the owners directly from the country's budget. In 2009, the sum awarded to them was $55 million. In all but a few of these countries (exceptions include the UK and Malta), the levy is imposed on all machines and blank materials capable of copying copyrighted works.
Under the directive, making copies for other people is forbidden, and if done for profit, can lead to a jail sentence.
Netherlands
In the Netherlands, citizens are allowed to make copies of their legally bought audio and video. This includes CD, SACD, as well as DVD and Blu-ray. These copies are called "home copies" and may only be used by the ripper. Public distribution of ripped files is not allowed.
Spain
In Spain, anyone is allowed to make a private copy of a copyrighted material for oneself, providing that the copier has accessed the original material legally.
United Kingdom
Private copying of copyrighted material is illegal in the United Kingdom.
In 2010, the UK government sought input on modernizing copyright exceptions for the digital age, and commissioned the Hargreaves Review of Intellectual Property and Growth. The review asserted that a private copying exception was overdue, citing that users were unaware of what was even legally allowed, and that a copyright law where "millions of citizens are in daily breach of copyright, simply for shifting a piece of music or video from one device to another" was not "fit for the digital age". However, the Review reasoned that no such collections are necessary when implementing a copyright exception for format-shifting: