In cryptocurrency, the block is the record of the most recent transaction. The data is permanently recorded in the blockchain when a block has been added. A new block is created each time a block is completed.
Each blockchain has only one copy of records of transactions that are distributed but owned by no single entity. This makes the blockchain transparent, and everyone involved is responsible for their own actions.
Every block contains three types of information:
Block header: This section includes all the metadata of the block. It consists of a version number, hash of the previous block, Merkle root hash, timestamp, and nonce value.
Transactions list: A list of validated and stored transactions in this block.
Block hash: A cryptographic hash of the header section.
The hash value is created by taking the data in a block and running it through a hashing algorithm. This creates a unique, fixed-length value that acts as an identifier for that block. If any changes are made to the data in a block, the hash value will be completely different, which will alert everyone that something is not right.