Practical applications

Storing data in the blockchain is expensive. However, there is a workaround, something you’ll learn later. For now, just assume you cannot store a lot of data on the blockchain. This means that you cannot build Reddit-like applications. So, what kinds of applications you can build on the blockchain? An application’s most important value is security from cheating. However, the data that’s stored shouldn’t be huge. What kinds of applications cannot store a lot of data but need to make sure the data cannot be tampered with easily?

Financial applications! The popular term for this is decentralized finance (DeFI). What we mean by financial applications are those that involve currencies, lending applications, exchanges between cryptocurrencies, futures, auctions, crowdfunding, and many more. They don’t need to store a lot of messages because transferring money means increasing the balance of an account and decreasing the balance...