Considering the fact that you have to be more than 30 years old to even have been alive when this game was released on home consoles, you may not actually know what is being referred to. Just know the Duck Hunt came bundled with many Nintendo Entertainment Systems back in 1985.
This game was quite simple as it only consisted of 2 ducks flying on to the screen that you needed to shoot with your "Zapper" that came bundled with your new NES set. There had never been anything like this available to home systems but then again Nintendo was truly innovating everything that we knew about video games at the time.
You only had 3 bullets and the ducks would get faster and more difficult to hit as the rounds went on.
This all seemed like magic as a kid, because how did the gun actually know what we were pointing at? As it turns out it is because at the exact moment that you pull the trigger just for a brief second the entire screen would turn black except for the areas around the ducks. The gun had a diode on it that could only determine if it was pointing towards a black or a white portion of the screen. If it detected white, you got a kill. If it detected black, nothing happened.
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It becomes more complicated involving multiple very fast frames when there were two ducks on the screen but when i think about how genius this is... it really is quite an innovation.
As a kid me and my friends would just move closer and closer to the tv as we tried to "cheat the system" however, as it turns out you could simply point the gun at any illuminated white surface such as a lamp, and you would get a kill every....single... time. Kind of takes the fun out of it though doesn't it.
I can't say that I really enjoyed this game because it was really just shooting some ducks... that was all there was to it. However, for anyone that is familiar with the game, you know how much you wanted to kill that damn dog that would laugh at you when you failed.