as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
explain the differences between blockchain and an ordinary database.
user
the differences between a blockchain and an ordinary database can be summarized as follows: 
blockchain is a distributed ledger, whereas a database is centralized. 
blockchain is secure and resistant to tampering, because it is protected by cryptography, whereas a database may not be as secure and can be manipulated. 
blockchain is public and decentralized, while a database is typically maintained by a single entity or organization. 
finally, blockchain is immutable, meaning that once a transaction has been processed, it cannot be changed or reversed, while a database can be updated or edited.
assistant