Imagine a blockchain as a digital ledger, like a shared online notebook. It records transactions in a secure, unchangeable way. It's called a blockchain because it's made up of blocks, each containing transaction information.
Here's how it works: when someone requests a transaction, like sending digital money, it's grouped with other transactions into a block. Before this block is added to the chain, it needs to be verified by multiple computers (nodes) on the network. These computers solve complex mathematical puzzles to ensure the transaction is valid.
Once verified, the block is added to the chain in a linear, chronological order. Importantly, once a block is added, it's nearly impossible to change any information inside it, making the blockchain very secure.
What makes it unique is that this process happens in a decentralized way across many computers, ensuring transparency and preventing tampering. This technology is not only used for cryptocurrencies but also for secure record-keeping in various fields.
