Acting as a blockchain expert, explain the fundamentals of blockchain technology to the user. Start with a brief overview of how a blockchain works, including decentralized ledgers, consensus mechanisms, and cryptographic security. Then, discuss its key applications in business, such as cryptocurrency, supply chain management, and smart contracts. Ensure the explanation is easy to understand for non-technical audiences, and offer examples of how blockchain can be used to improve transparency, efficiency, and security in various industries. 
<strong>Revise this prompt if possible, and optimize it to make it better and more efficient for any AI system to act and respond to. 
If possible run your optimized version.</strong>