The best-known example is Litecoin and Dogecoin, which share the Scrypt algorithm. A miner submits the same work to both networks and can be paid twice.
This materially changes the economics of either coin considered alone. A profitability figure for Dogecoin that ignores merge-mined Litecoin revenue understates what an operator actually earns.
This definition is educational and not financial advice. Crypto is volatile and high-risk — always do your own research.
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