Region coding is how Hollywood studios stagger DVD movie releases across the planet. These codes ensure that one country doesn't get a DVD movie before the same movie is out in that country's theatres. In their corporate omniscience, movie studios have carved the planet into regions with each region having a specific code.

All DVD players and discs have region codes. A DVD player and disc must be of the same region or the disc will not play.

If you want to watch movies from other countries, you need a multiregion DVD player. This will allow you to play any disc from any region. However, because TV standards differ, you might need a specialized NTSC/SECAM/PAL TV or a DVD player that can output any signal to the standard your TV accepts. TechTV