Region 4

DVD (commonly digital video disc) region codes are a digital rights management technique designed to allow film distributors and television companies to control aspects of a release, including content, release date, and price, according to the region.

This is achieved by way of region-locked DVD players, which will play back only DVDs encoded to their region (plus those without any region code). The American DVD Copy Control Association also requires that DVD player manufacturers incorporate the regional-playback control (RPC) system. However, region-free DVD players, which ignore region coding, are also commercially available, and many DVD players can be modified to be region-free, allowing playback of all discs.

DVDs may use one code, a combination of codes (multi-region), every code (all region) or no codes (region free).

DVDs in Hispanophone Latin America and Mexico use both the region 1 and region 4 codes.

DVDs sold in the Baltic states use both region 2 and 5 codes.

Region 0 (playable in all regions except 7 and 8) is widely used by China and the Philippines.

Most DVDs in India combine the region 2, region 4, and region 5 codes, or are region 0; Indian Disney discs contain only the region 3 code.

European region 2 DVDs may be sub-coded "D1" to "D4". "D1" are the United Kingdom–only releases; "D2" and "D3" are not sold in the UK and Ireland; "D4" are distributed throughout Europe.

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" (RCE).

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