DVD video discs may be encoded with a region code restricting the area of the world in which they can be played. Discs without region coding are called all region or region 0 discs.
The commercial DVD player specification requires that a player to be sold in a given place not play discs encoded for a different region (region 0 discs are not restricted). The purpose of this is to allow motion picture studios to control aspects of a release, including content, release date, and, especially, price, according to the region. Many DVD players are or can be modified to be region-free, allowing playback of all discs.
|0||Informal term meaning "worldwide". Region 0 is not an official setting; discs that bear the region 0 symbol either have no flag set or have region 1–6 flags set.|
|1||Canada, United States; U.S. territories; Bermuda|
|2||Western and Central Europe; Western Asia; Egypt, Japan, South Africa, Swaziland; British overseas territories, French overseas territories|
|3||Southeast Asia; South Korea; Non-mainland China (Hong Kong)|
|4||Oceania; Central and South America; Caribbean; Mexico|
|5||Ukraine, Belarus, Russia, Africa, Central and South Asia, Mongolia, North Korea.|
|6||Mainland China, Hong Kong|
|7||Reserved for future use (found in use on protected screener copies of MPAA-related DVDs and "media copies" of pre-releases in Asia)|
|8||International venues such as aircraft, cruise ships, etc.|
|ALL||Region ALL discs have all 8 flags set, allowing the disc to be played in any locale on any player.|
DVDs sold in the Baltic States use both region 2 and 5 codes. DVDs sold in Japan use the region 2 code while Hong Kong, Macau and Taiwan use the region 3 code, with Hong Kong sharing region 6 for releases after the reunification. Region 0 (playable in all regions, except 7/8) is widely used by China, the Philippines, Hong Kong, Macau, and Taiwan. DVDs in Latin American Spanish use both the region 1 and region 4 codes. Most DVDs in India combine the region 2, region 4, and region 5 codes; Disney discs contain only the region 3 code.
Any combination of regions can be applied to a single disc. For example, a DVD designated Region 2/4 is suitable for playback in Western Europe, Oceania, and any other Region 2 or Region 4 area. So-called "Region 0" and "ALL" discs are meant to be playable worldwide.
The term "Region 0" also describes the DVD players designed or modified to incorporate Regions 1–6, thereby providing compatibility with most discs, regardless of region. This apparent solution was popular in the early days of the DVD format, but studios quickly responded by adjusting discs to refuse to play in such machines. This system is known as "Regional Coding Enhancement".
It may be difficult for American companies to enforce their copyright rights in the countries in the Region 5 area, and thus they may release Region 5 DVDs earlier than Region 1 DVDs to encourage consumers to opt for a legal version, rather than a pirated copy of a DVD screener. Many of the countries in the region 5 area were historically either incapable of or unwilling to uphold American copyrights. In many of the countries in the Region 5 area, war or extreme poverty make intellectual property rights a low-priority interest for the governments. See also R5 (bootleg).
However, it is easy to work around the scheme. A region-free player tries to play a disc using the last region that worked with the previously inserted disc. If it cannot play the disc, then it tries another region until one is found that works. RCE could thus be defeated by briefly playing a "normal" region 1 disc, and then inserting the RCE protected region 1 disc, which would now play. RCE caused a few problems with genuine region 1 players.
As of 2007, many "multi-region" DVD players defeat regional lockout and RCE by automatically identifying and matching a disc's region code and/or allowing the user to manually select a particular region. Some manufacturers of DVD players now freely supply information on how to disable regional lockout, and on some recent models, it appears to be disabled by default. Programs such as DVD Shrink are also capable of removing RCE protection, provided the operator knows what the region of the disk actually is. If the region is specified correctly, the copy will play in any region.
Another purpose is controlling release dates. One of the traditions of movie marketing that the advent of home video threatened is the practice of releasing a movie (to theaters) later in some countries than in others. The threat from video tape was muted by the coincidence that television broadcast standards, and thus video tape formats, were for historical reasons regional. But apart from region coding, the DVD format is meant to be playable everywhere.
Movie publishers misused region coding when they released older material with full region coding—there being no requirement, per the stated cinema-blockout justification provided, to restrict sales to certain countries. There are concerns, voiced by the European Union, that region coding was solely an attempt to enforce price differentials.
However, if the player is not region-free, it can often be unlocked with an unlock code entered via the remote control. This code simply allows the user to change the factory-set configuration flag to another region, or to the special region "0". Once unlocked this way, the DVD player allows the owner to watch DVDs from any region. Many websites exist on the Internet offering these codes, often known informally as hacks.
Other software, known as DVD region killers, transparently remove (or hide) the DVD region code from the software player. Some can also work around locked RPC-2 firmware.
Since North America and Japan both used NTSC, different regional codes could be used to separate the 2 regions: the US using Region 1 coding and Japan using Region 2. Europe also uses Region 2 coding. These artificial limitations were not present in earlier LaserDisc and video cassette technology. Using the older LaserDisc or video cassette system, one could purchase video media in Japan and easily view it in the US. Another example is playing DVDs from Mexico and Australia on a DVD player that is flagged for Region 4, despite the different formats between the two countries (Much of Latin America uses NTSC [including Mexico], while much of Oceania [including Australia] uses PAL).
On a side note: The audio for NTSC and PAL were along the same track in magnetic video cassettes, it is not uncommon to place a PAL cassette in an NTSC cassette player (or NTSC cassette in a PAL player) and hear the audio clearly (although at incorrect speed) with distorted video. Region encoding in digital players helped block this as well.
With newer-style digital televisions and the use of variable frequency and resolution monitors, NTSC, PAL/SECAM are really no longer necessary. With the advent of internet and access to digital video online, region encoding is finding hurdles of its own and may slowly fade away the way NTSC, PAL/SECAM are.
Note that many people confuse Regional Coding with a form of Encryption. In reality, Regional Coding is an even cruder form of imposing geographical limitations on physical media traveling across borders, whereas the CSS copy protection used on DVD was designed to prevent the disc's content being copied - not to regulate where in the world it is played. As such, references to "Region Encryption" are a misnomer.