Blockchain is a distributed database that maintains a continually growing list of records that can be verified using hashing techniques.
Blockchain implementations have a handful of defining characteristics, it’s:
- append-only system (meaning records in the database cannot be changed, records can only be added to the ledger);
- replicated in multiple locations;
- crypto-secured through a public or private key infrastructure;
- uses hashes.
The hash functionality is particularly important as each individual transaction is hashed into the chain, and each block, which contains a bunch of transactions, is also hashed, which links it to the previous block. The moment anyone tries to change a transaction, everyone who has access to the chain would know immediately that it’s been tampered with because the hash wouldn’t match.
This creates a platform where multiple parties can share data, but all have proof that past records have not been changed. It’s quite a remarkable platform, but it’s in the very, very early stages of maturity.