A blockchain is a type of distributed ledger technology (DLT) that stores data in a chain of blocks. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. By design, blockchains are inherently resistant to modification of the data. The blockchain is a shared, immutable ledger that records transactions between two parties in a permanent, verifiable, and transparent way.
For example, let’s say that two people, Alice and Bob, want to make a transaction. Alice has some cryptocurrency that she wants to transfer to Bob. First, Alice and Bob will agree on the terms of the transaction, including the amount of cryptocurrency that Alice will send to Bob. Then, Alice will initiate the transaction by broadcasting her request to the network.
The request will be validated by the network using consensus algorithms, and once the transaction is validated, it will be stored in a block on the blockchain. The block also contains a cryptographic hash of the previous block, a timestamp, and other transaction details. Once the block is added to the blockchain, it cannot be modified or deleted, and the transaction is complete.