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51% Attack

In a 51% attack, a single entity or a group of entities controlling more than 50% of the total computing power of the network can take control of the network by generating a longer blockchain than the rest of the network.

This means they can reverse transactions, double-spend coins, prevent other miners from validating blocks, and even exclude other participants from the network. This can lead to the loss of funds and the breakdown of the trust in the network.

To prevent 51% attacks, blockchain networks rely on distributed consensus mechanisms like Proof-of-Work (PoW) or Proof-of-Stake (PoS) that make it extremely difficult for any single entity or group to control the network. However, in some cases, smaller blockchain networks with fewer participants may be vulnerable to such attacks