[Quall999]

It is the format for each region's display standards. The different encodings have separate methods for storing colors, and display at a different frequency. That is the technical description.

The different encodings are used by retail companies to differentiate regions, mostly. A lot of this has to do with trade rights as well. Retailers disallow importing electronics from other regions by locking them into displaying and interpreting only one signal.

If a game or system were to be released in the UK an entire year before the US, then I would not be able to import and play it. The game would not work on my system, and a system would not work on my TV. If the game was cheaper in the UK, I would not be able to play it if I were to import it. Companies are not going to produce different hardware though. Instead, then will produce hardware that can render both modes, and lock it to a region.