G'day Gentlemen,
Actually there are quite a few 'regions' in the world as far as DVD goes. Here in Australia we are region 4.
The 'multi region' DVD players (or the ones that have been 'hacked' as such) are an attempt to save a few bucks (read $millions) by the studio's.
If a film is released in the U.S.A., it usually takes anywhere up to 6 months before it is playing here.
Multi zone players allow you to buy a DVD disc from the 'States, or where ever, and be playing it in the comfort of your own home before it is released on the big screens of your home country.
Now with TV rights, video (sorry, DVD ) rentals and sales etc. at risk, the studios thought of a clever way to foil you!
The next thing is the coding of the DVD's themselves so that if a 'multizone' machine is detected, a disable signal will be sent to the machine and an "access denied" message will result. Don't ask me about the technical side of this, I haven't a clue, But this was reported in the Australian trade paper, "Cinema Papers" in February. Braveheart was the first title released in Aust. with this feature.
So, be careful out there, and play nice.
Big brother is watching!