A blockchain is a digital ledger that is decentralized, distributed, and publicly accessible. Its main function is to record transactions across a network of computers in a secure and tamper-proof manner.
One of the key features of a blockchain is its immutability. Once a block of data has been added to the blockchain, it cannot be altered retroactively without changing all subsequent blocks and obtaining the consensus of the network. This ensures the integrity of the data stored on the blockchain, making it a reliable and trustworthy system for recording transactions.
The decentralized nature of the blockchain means that there is no single point of control or failure, making it more secure and resilient against cyber attacks. Additionally, the distributed nature of the blockchain ensures that there is no need for a central authority or intermediary to oversee transactions, making it more efficient and cost-effective.