Pink Floyd is kind of interesting because people who love them all seem to love something different about them. To that end, it's hard to say what is the "best" album(s). The most commercially successful or popular albums were probably Dark Side, The Wall, and Wish You Were Here probably in that order. You should listen to it all and make your own decision. This band will either speak to you or it won't and what you hear will be unique to you. You will then have no questions about what are the best album(s).
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If ignorance were painful, half the posters here would be on morphine drips.
Everyone playing WoW knows everything about playing two classes: 1) their own and 2) Hunters