After reading the discussion between the two experts in the comments, I’ve been thinking about one question: The most unique invention of Bitcoin is actually Proof of Work (POW). The greatest thing about Bitcoin is: sustainable, attack-resistant, and permissionless consensus. And what POW achieves is: For the first time in human history, it ties 'real-world, unforgeable physical costs' to a completely open, distributed consensus system in a sustainable and verifiable way. To put it in simpler terms: Bitcoin is like a public ledger that no one controls, with just one rule: whoever spends the most real money first gets to be the temporary bookkeeper. Being the bookkeeper comes with rewards, but if you mess up the records, the money you spent earlier is wasted. No approvals, no management. POW isn’t a technological or cryptographic innovation; it’s the perfect application of economics and game theory. It doesn’t assume participants are good people; it only assumes people are selfish. The system designs rule-following as a profitable behavior and bad actions as high-cost, low-reward behaviors. Mining rigs and hash power are just tools to prove that real-world costs have been paid, because electricity, hardware, and time are unforgeable. This anchors the digital world to the real world.