(click for larger image)Here is a map of the different video formats worldwide. There are 3 major video formats in the world. These are NTSC (North American), Pal (British) and Secam (French).
There are some small details to look out for. Most of Africa uses Secam because of the French legacy. However most of Southern Africa is Pal as is most of Asia. A big exception being that Japan and South Korea are NTSC. The Middle East is also an interesting mix: Saudi Arabia, Jordan and Israel are NTSC, whereas Iran and Iraq are Pal and Lebanon and Syria are Secam.
Don't ask me why these different formats exist in these different regions, but I would venture to say it has to do with the leftovers of 19th century geopolitics... largely old British colonies use Pal and French ex-colonies (or territories) use Secam. The great thing about Japan using NTSC is that they show a lot of US TV programs in Japan, whereas Europeans need to transcode the content first adding to cost. (WW2 and Korean War, respectively accounting for Japan and Korea using NTSC)