A 51% attack happens when a single entity or group features management of greater than half of the computational energy (hash fee) on a blockchain community. With majority management, the attacker can manipulate the blockchain by reversing transactions, double-spending cash, or stopping new transactions from being confirmed.
Such assaults undermine the belief and safety of the community, probably resulting in monetary losses and a lack of confidence amongst customers. Whereas giant networks like Bitcoin are comparatively immune to 51% assaults resulting from their dimension and decentralization, smaller networks will be extra weak.