In the blockchain, the random hash used is also called hash. Hash is a digital signature technology, and a fixed-length output can be obtained by inputting data of any length into an algorithm.

The hash algorithm is irreversible, which means that the original data cannot be derived from the hash value. This makes the hashing algorithm very suitable for digital signature and data verification.

In blockchain, hash algorithm is used to generate unique hash values of blocks to identify each block. These hash values are connected together to form a chain, which constitutes a blockchain. This way makes the blockchain very safe, because any tampering with the block will lead to the failure of the whole transaction.