One of the most requested DVD player features is multi-region playback the ability for a DVD player to play discs intended for other countries. The reason for this is because DVDs are encoded to play in their set "region" or geographical location, so having a multi-region DVD player instantly allows you to purchase and play DVD titles from anywhere in the world.
Having the ability to play DVDs from anywhere in the world instantly gives you access to a larger catalogue of DVDs. In addition to this you can often purchase DVDs from another country that contain more material; this may be anything from extra scenes and audio commentary to a different cut of the film.
The world is split into eight regions and a "free" region 0. Europe is region 2, while North America and Canada are region 1.