51% Attack !

Today we understand the meaning of the term 51% attack.

Bitcoin miners in fact use their powerful computers to keep the bitcoin network alive by managing and processing all transactionslike checking that the users dont create any double spending trouble on the network.
This very important work, which guarantees the functioning and trust in bitcoin, is done by controlling the blockchain in its entirety.
To give an example, in the case of a transaction on the bitcoin blockchain from user A to B, the miners will check that the transaction is valid, that there are on the address of user A those bitcoins that he wants to move towards the address of user B.
If most miners certify the transaction as correct, then it will be confirmed and entered on the blockchain.

Now, if you had more than 50% of the computing power of the blockchain, it could theoretically be manipulated, carrying out double spending and other types of fraud such as preventing any transactions from specific addresses or eliminating other miners from the network.
The problem is real especially if the computational power of the blockchain is concentrated in the hands of a few connected and colluding hands. In this, the decentralization of mining should avoid this problem. If we think in the event that most of the computational power is in the hands of two or three large companies, the problem of dealing with a cartel is real.

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