What is the difference between P-1, P-2, and P-3 status?

There are three categories for P-visas:

"I am both lucky and proud to have been chosen to become a future U.S. citizen. I can't wait to..."

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"This is a once in a lifetime chance to be able to live in America and experience the rich and..."

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"Dear The American Dream Team: Thank you so much for your support and the professional counselling."

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"Thank you for your lovely Certificate of Entry for the U.S. Green Card Lottery. I want you to know that..."

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"Here They Are! Our green cards did arrive. Those cards are our tickets to start a new life. It took..."

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"The American Dream helped me to realise my dream. I have always dreamed about living in the US, but so..."

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"A couple years ago, I heart about The American Dream and decided to participate in the GreenCard lottery. I have..."

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"Dreams really do come true with the help of The American Dream. We will head to Florida in September 2010...."

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"Thank you, American Dream, for the first-class service and the great assistance. My dream to work in the USA becomes..."

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"This can’t be true! Something like that sentence was my reaction when being told the good news by The American..."

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