From "Twenty-Five Years of Post-it Notes":
[T]he Post-it Note was more than just a practical tool--it was also a psychological one. Compared to the clunky machines of the 1980s that generated all those documents, it was a vision of high-tech minimalism. Its edges were sharp and square, with no ugly binding, no perforations, no metal rings. Its color, a subtle but attention-getting yellow, was somehow like the color of thought itself, a lightbulb going off in your head. Devoid of any other graphic elements, it had the effect of a clean, calming, blank screen. And, yet, for all its streamlined efficiency, it was playful and user-friendly . . . .You can read the article by clicking here.