DVDs are UK editions and Region 2. They play on standard players in the UK, Europe, Japan and the Middle East, but not on a standard player in the United States, Canada, Australia, New Zealand, Singapore, Hong Kong or South Korea unless the player is region-free.
Blu-rays are usually Region B, which plays in the UK, Europe, Australia, New Zealand and the Middle East. Region B discs will not play on a standard player in the United States, Canada, Japan, South Korea, Singapore or Hong Kong. Some titles are region-free, so check the product description before ordering.
4K Ultra HD discs are almost always region-free and play anywhere.