Blockchain is basically a way for many people to keep track of information together, without needing one person in charge to verify the information.  

To go into more detail: blockchain is a decentralised (meaning the power and control are spread out across everybody) digital ledger (like an online notebook that everyone has a copy of) that records transactions across a network of computers, making it difficult for the data to be tampered with or changed (because everyone has a copy of the ‘notebook). Each block in the chain contains a record of multiple transactions and, once verified by the network, they are added to the chain in a chronological order. This creates a "chain" because each new page links to the one before it, like a chain of information that you can't break apart... hence the name blockchain.  

The way blockchain works is by using a peer-to-peer network instead of relying on a central authority: this means all the computers (nodes) in the network talk directly to each other as equals. So,there is no single point of failure and the data is secure as it is distributed across multiple nodes.

Through valid transactions, new blocks are added to the chain and updated on all nodes in the network. This creates a transparent system where all participants have access to the same information, making it virtually impossible for anyone to manipulate or defraud the system.

This differs from the traditional centralised systems where a central authority (like a boss) has control over the data and can potentially manipulate it for their own benefit.

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