what does the first one refer to?
In the United States, the Triple Crown of Thoroughbred Racing, commonly known as the Triple Crown, is a title awarded to a three-year-old Thoroughbred horse who wins the Kentucky Derby, Preakness Stakes, and Belmont Stakes.
Triple Crown of Thoroughbred Racing (United States)
In the United States, the Triple Crown of Thoroughbred Racing, commonly known as the Triple Crown, is a title awarded to a three-year-old Thoroughbred horse who wins the Kentucky Derby, Preakness Stakes, and Belmont Stakes. 
who won the triple crown before american pharaoh Affirmed. how did it get the name? : American Pharoah's name is inspired by that of his sire, the Nile, and his dam's sire, Yankee Gentleman. The horse's name also acknowledges his owner Amhed Zayat's own Egyptian-American background. what is it about? American Pharoah  is an American Thoroughbred racehorse. name a few race events it has participated in? American Triple Crown and the Breeders' Cup Classic.
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Triple Crown of Thoroughbred Racing (United States) [SEP] Introduction
In the United States, the Triple Crown of Thoroughbred Racing, commonly known as the Triple Crown, is a title awarded to a three-year-old Thoroughbred horse who wins the Kentucky Derby, Preakness Stakes, and Belmont Stakes. The three races were inaugurated in different years, the last being the Kentucky Derby in 1875. The Triple Crown Trophy, commissioned in 1950 but awarded to all previous winners as well as those after 1950, is awarded to a Triple Crown winner. The races are traditionally run in May and early June of each year, although global events have resulted in schedule adjustments, such as in 1945 and 2020.