What is a 51% Attack? Mechanism and Impact in Crypto

A 51% Attack occurs when an entity controls more than 50% of a blockchain's computing power, allowing them to manipulate transactions and cause double spending. This attack can lead to mining monopolies and transaction denial-of-service. While such attacks are highly unlikely on major blockchains like Bitcoin, they remain a critical security concern. Blockchain projects continue to address this issue while navigating the blockchain trilemma of decentralization, scalability, and security.