Depends what you want to do with your output and what devices will be used to play things back. For technical explanations of both systems see wikipediahttp://en.wikipedia.org/wiki/Ntschttp://en.wikipedia.org/wiki/PAL
You can also google "pal vs ntsc" and you will get lots of comparisons, for example:http://www.diffen.com/difference/NTSC_vs_PALhttp://www.steves-digicams.com/knowledg ... pal.html#b
Think of the systems like 2 different languages for speaking "video". In NZ you can speak english and most people will understand try to do this in France and you are likely to be met with a blank face. So if your camera speaks in PAL and is talking to an NTSC display device you don't get what you expect.
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