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BTC/Mining.md

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+**Light Nodes vs. Full Nodes**: In the Bitcoin network, most nodes are lightweight nodes. If you only want to make transactions and are not interested in mining, there is no need to run a full node. During mining, if a miner detects that someone else has already mined a block and extended the longest chain, they should immediately abandon their current work and restart the mining process.
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+**Mining Has No Memory**: Mining itself does not have memory. Previous work does not affect future mining efforts, so even if earlier work becomes invalid, it is not wasted.
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+**Bitcoin System Security**:
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+- **Cryptographic Assurance**: Without someone else's private key, no one can forge a legitimate signature to transfer Bitcoin from another account.
+- **Consensus Mechanism**: Ensures that malicious transactions are not accepted by the system.
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+**Evolution of Mining Equipment**:
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+- Mining equipment has evolved from general-purpose CPUs to GPUs, and now to specialized ASIC chips. As mining difficulty increased, using general-purpose devices became inefficient, leading to the emergence of specialized mining hardware.
+- ASIC chips are designed specifically for mining certain cryptocurrencies. While they increase mining efficiency, they also raise the entry barrier, which goes against Bitcoin's original decentralized vision.
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+**Emergence of Large Mining Pools**:
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+- Individual miners often face unstable incomes, leading to the development of mining pools. Mining pools can be centralized (data center-like) or distributed (miners from different organizations). The pool allocates tasks, and miners are rewarded based on proof of work.
+- Mining pools also face challenges, such as intentionally disrupting the pool by discarding mined blocks.
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+**51% Attack and Transaction Blocking**:
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+- A mining pool that controls over 51% of the network's  can perform a fork attack, rolling back previously confirmed transactions, which poses a major threat to the system's security. Additionally, an attacker can block transactions from a specific account by preventing its transactions from being included in the longest valid chain.
+- However, stealing Bitcoin from others is impossible without having the private key, as the network will not recognize unsigned transactions.
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+**Pros and Cons of Mining Pools**:
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+- **Pros**: Mining pools provide more stable income for miners and reduce their workload.
+- **Cons**: They threaten the security of the blockchain system, making 51% attacks more feasible.