Provide a detailed explanation of what blockchain technology is, how it works, its key features, and some real-world applications. Your response should contain at least 5 paragraphs. Paragraphs are separated with the markdown divider: ***. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. At the end of your response, please explicitly add a postscript starting with *P.S.*. In your response, the word "decentralized" should appear at least 3 times.
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