Cryptographic Hashing

Cryptographic hashing is a mathematical process that takes the transactions in a block, the hash value of the previous block in the chain, and other relevant block data as inputs into a hash function, and generates a unique string of alphanumeric characters that serve as a representation of that data—i.e., the hash value. Importantly, if that data were altered in the slightest way, the hash function would generate a completely different hash value, making any tampering immediately evident.