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51% Attack

51% attack is a significant security concern in the cryptocurrency world. It occurs when a single entity or group gains control of more than 50% of a blockchain network’s computational power.

With this majority control, the attacker can manipulate transactions, double-spend coins, and potentially undermine the network’s integrity. By creating an alternate version of the blockchain, the attacker can invalidate legitimate transactions, leading to financial losses for other users and damaging the blockchain’s credibility.

Preventing a 51% attack often requires a decentralized network with widespread mining participation, making it computationally infeasible for a single entity to control the majority. Blockchain networks employ various consensus algorithms, such as proof-of-work and proof-of-stake, to mitigate the risk of 51% attacks and maintain the network’s security and trustworthiness.