Blockchain is a method of storing information in such a way that it is difficult or impossible to modify, hack, or trick the system.
Blockchain is defined as a chain of information-containing blocks. The technique is intended to timestamp digital documents so that they cannot be backdated or tempered. The goal of blockchain is to fix the issue of duplicate records without the use of a central server.
The blockchain is used for the safe transfer of items like money, property, contracts, and so on without the need for a third-party mediator such as a bank or government. It is extremely difficult to alter data after it has been stored within a blockchain.
Sources:
https://www.guru99.com/blockchain-tutorial.html
https://www.euromoney.com/learning/blockchain-explained/what-is-blockchain