Many people have been asking what blockchain is, so let me explain it from my own perspective.

In reality, blockchain isn’t as complicated as people think. It’s a technology that helps us transmit information without needing a middleman, with very strong security. Put simply, blockchain is the process of linking blocks of data into one long chain, making it extremely difficult for anyone to tamper with the information.

What’s interesting is how blockchain works. It has fairly strong protective mechanisms. The first is the Hash Code, which is the unique identifier of each block—no two blocks have the same hash. If someone tries to modify the data in a block, the hash changes immediately, and the next blocks will no longer accept it. Imagine having to modify all the blocks in the chain to match before the new block is added—this becomes increasingly difficult.

Another important factor is the Consensus Mechanism that Bitcoin uses: Proof-of-Work. This system gives about 10 minutes to solve the cryptographic puzzle and create a new block. If someone were to hack it, they’d have to race against the entire network and solve all the cryptographic puzzles in time. It’s extremely hard to do.

And one more thing that makes blockchain so powerful is the Peer-to-Peer network. There is no single central party that fully controls everything. But every user is a Node that checks and verifies each other. You would need to control more than 51% of the nodes in order to control the system—and in practice, this is virtually impossible.

When it comes to types of blockchain, there are several. There are public blockchains like Bitcoin and Ethereum, which are open for everyone to join. There are also private blockchains like Hyperledger, which are controlled by a single organization. In addition, there are hybrid and consortium blockchains that combine both approaches. Each type has different purposes and use cases.

So what are the strengths of blockchain? The biggest one is high security. Once data is encrypted, it can’t be altered. It offers transparency, with no middleman controlling authority, and it reduces costs because you don’t have to pay fees to intermediaries. It’s also traceable and highly efficient because many processes can be automated.

But there are also weaknesses that need to be considered. One is scalability: blockchain still can’t support as much data as we need. Theoretically, it could be hacked, but in practice it’s so difficult that there’s almost no chance. It also consumes a lot of energy because it requires heavy computation, and there is still no serious oversight from major organizations.

Blockchain is used in many real-world applications. In finance, for example, Thailand’s central bank has an Inthanon project that uses blockchain for digital Baht. JMART’s JFIN project uses blockchain to store customer data and Credit Score in the supply chain. IBM has created Food Trust Blockchain to allow consumers to verify the origin of raw materials. In terms of voting, blockchain can help make voting systems more transparent and prevent cheating effectively.

If we summarize it simply, what is blockchain? It is a technology that changes the way we store and exchange information—by decentralizing control and increasing security—so we no longer need to rely on middlemen. Whether used in crypto or other fields, it’s a technology that promises to bring about many changes in the future.