What is Blockchain?

Blockchain is a digital notebook that everyone can see but no one can erase. Imagine: A large notebook stands in front of everyone in a classroom. Everyone can write in it, but once written, it cannot be erased.

The biggest feature of this technology is that it is decentralized. This means no single person or institution controls it. Thousands of computers hold the same notebook, and when new information is added, all computers update. This makes cheating almost impossible.

The most well-known use of blockchain is cryptocurrency. Digital currencies like Bitcoin and Ethereum run on this technology. But blockchain is used not only for money but also for voting systems, supply chain tracking, and digital identity verification.

As a simple analogy: Blockchain is like a bulletin board in an apartment building shared by neighbors. Everyone can leave notes, everyone can see the notes, but once posted, you need the approval of the entire building to change it.