PAL is the technology that is used to format video signals on Australian/NZ/UK televisions and VCRs, NTSC is yours Canada's and Japan's.
NTSC=Never The Same Color (Twice). It's another example of Americans assuming they can do a better job by creating their own standard for doing things instead of just going along with the team effort and making one standard better. NTSC uses 525 lines (if you get really close to an analog TV set, you can see the horizontal lines that make up the image). The more lines, the sharper the image can be. NTSC has been adopted by United States, Canada, Greenland, Mexico, Cuba, Panama, Japan, South Korea, the Philippines, Puerto Rico and most of South America. Basically anywhere America had dominant influence, NTSC got adopted.
The other two standards are PAL which is used by virtually everyone else and SECAM which was developed by the silly French as a matter of national pride. Both PAL and SECAM use 625 lines, so you get a sharper image already, and they come closer at 25 frames per second to the film standard of 24 frames per second, which makes converting film for DVDs and broadcasts far easier. The NTSC system requires 30 frames per second, and when they convert film to broadcast or DVD, they have to jump through hopes. Since the capitalist western half of Europe used PAL, eastern Europe and the Soviet Union went for SECAM just to make broadcasts between east and west incompatible (in color at least). Post Cold War, a lot of eastern European countries are switching to PAL.
The only downside to PAL/SECAM is their reliance on the 50hz/50 fields per second timing standard (locked to the 50hz power rate). Americans who are used to NTSC can usually see the flaw straight away when they see a PAL/SECAM transmission because it flickers more than the NTSC system. Since we are used to NTSC, when we see the other standards, we are more sensitive to the flashing phenomenon.
Anyway, it's all rapidly becoming irrelevant as we approach HDTV conversion which throws away the analog color standard issue. Digital broadcasts work much differently. But don't worry - we're about to repeat the same mistakes all over again with digital radio. While every country around, including Canada, has chosen the Eureka digital radio standard, once again we decided we could do better and we came up with IBOC - In Band On Channel. Eureka is a fully digital radio standard, grouping stations together and transmitting them on a much higher frequency. IBOC transmits an analog and digital signal at the same time on the same frequency. It's terrible, causing interference for analog and digital users, especially on the AM dial. Eventually this means Canadian radio will be totally incompatible with American radio unless car manufacturers build support for the two totally different systems. More bungling....
BTW, many of the cheapest DVD players out there made in China happily handle NTSC and PAL DVDs quite fine and convert them for display on either set. I can rent and watch British DVDs using the PAL format and see them in color. Of course I don't get the better resolution, but they are quite watchable.