The title "King of Cryptocurrency" is usually given to Bitcoin (BTC) — it was the first cryptocurrency, launched in 2009 by the mysterious Satoshi Nakamoto, and it still dominates the market in terms of value, influence, and adoption.
Other strong contenders like Ethereum (ETH) have carved out their own kingdoms (like smart contracts and decentralized apps), but Bitcoin remains the undisputed king in most people's eyes.
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