Currently, there are six global region codes that identify a DVD's compatibility with the players typically sold in that region, or with multi-region players.
The following are the six regions and their corresponding numerical equivalent:
1- US, US Territories and Canada.
2- UK, Europe, Japan, South Africa and the Middle East including Egypt
3- Southeast Asia, East Asia including Hong Kong
4- Australia, New Zealand, Pacific Islands, Central America, South America and the Caribbean
5- Former Soviet Union, Indian sub-continent, Africa, North Korea and Mongolia
Region 0 (or "region free") is compatible with DVD players from any of the six regions.
They also require an NTSC-compatible television. NTSC is the standard picture format in North America, and differs from the PAL format adopted in Britain and Europe. Region 1 DVDs are usually presented in NTSC format, so you should ensure that your TV is capable of reading the NTSC signal before purchasing Region 1 DVDs.
Regional Coding Enhancement (RCE)
Regional Coding Enhancement (RCE) has been added by some film studios (specifically Warner and Columbia) to selected Region 1 DVDs, with the intention of preventing these discs from playing on some multi-region DVD players. We are therefore unable to guarantee that all Region 1 discs will be compatible with all multi-region players.
Worldwide, there are three recording standards for commercially released videos. Each is unique and incompatible because of differing rates of frame-per-second delivery.
Is used in most European countries and regions of Asia.
Abu Dhabi, Afghanistan, Albania, Algeria, Angola, Argentina, Ascension Island, Australia, Austria, Azores, Bahrain, Bangladesh, Belgium, Bosnia Herzegovina, Botswana, Brunei, Cameroon, Canary Islands, Cape Verde, Cayman Islands, China (Peoples Republic), Christmas Island, Cook Island, Croatia, Cyprus, Denmark, Dubai, Easter Island, Eritrea, Ethiopia, Falkland Islands, Faroe Islands, Finland, Gambia, Gaza & West Bank, Germany, Ghana, Gibraltar, Greenland, Guinea, Guinea-Bissau, Holland, Hong Kong, Iceland, India, Indonesia, Ireland, Israel, Italy, Jordan, Kenya, Kuwait, Lebanon, Lesotho, Liberia, Liechtenstein, Luxembourg, Macao, Macedonia, Madeira, Malawi, Malaysia, Maldives, Malta, Montenegro, Mozambique, Namibia, Nepal, Netherlands, New Zealand, Nigeria, Norfolk Island, Norway, Oman, Pakistan, Papua New Guinea, Paraguay, Poland, Portugal, Qatar, Sardinia, Seychelles, Sierra Leone, Singapore, Slovenia, Solomon Islands, Somalia, South Africa, Spain, Sri Lanka, Sudan, Swaziland, Sweden, Switzerland, Syria, Tanzania, Thailand, Tonga, Tristian Da Cunah, Turkey, Uganda, United Arab Emirates, United Kingdom, Vanuatu, Vatican, Yemen, Yugoslavia, Zambia, Zanzibar and Zimbabwe.
NTSC format is used in the United States and Canada. This format is not compatible with the PAL format used in Europe and other parts of the world.
USA, Antigua, Bahamas, Barbados, Belize, Bermuda, Bolivia, Burma, Canada, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Greenland, Guam, Guatemala, Guyana, Honduras, Jamaica, Japan, South Korea, Mexico, Netherlands Antilles, Nicaragua, Panama, Peru, Philippines, Puerto Rico, St. Vincent & the Grenadines, St. Kitts, Saipan, Samoa, Surinam, Taiwan, Tobago, Trinidad, Venezuela, Virgin Islands.
The above was gathered from various older sources, so discrepencies in spelling or political changes are unintentional.