A 51% attack is linked to mining and specifically to the work test algorithm, under which many blockchains work and in which many cryptocurrencies are handled.
What Is a 51% Attack?
In the case of the Proof of Work consensus mechanism, the miners use their computational power to verify transactions and keep the system safe, so that, if there is an approval by all users, the operation it is executed and added to the last block of the chain.
This work is done in the blockchain, where the public record of all these transactions is maintained and because of its decentralized status, it generally allows the miners to group together to accumulate more power than they would have individually, thus adding more efficiency to the process.
A 51% attack occurs when a person or group of miners acquires control over the computing power of 51% of the entire network. That is to say, to procure with greater mining capacity than the rest of the members of the ecosystem, being able to carry out unfavorable alterations for the network and its technology.
Should You Worry About It?
Carrying out an attack of 51% requires an enormous amount of time and resources, which does not result in something suitable or practical for any interested party and as an added obstacle, the duration of the attack would be practically minimal after it becomes evident.
Many members of the community currently believe that an attack of this type to Bitcoin Blockchain would be unfeasible because of the amount of energy needed and above all because it would also be immediately counteracted by users, since at this point and being aware of the consequences, to generate an increase in the percentage of power in a group of miners, they would be responsible for redistributing that power to maintain balance.