What is blockchain?

Blockchain is like a shared notebook that everyone can write in, and no one can change what’s already written.

Imagine you and your friends are keeping score for a game. Every time someone wins a round, they write it down on the notebook. But instead of just one person holding the notebook, all of you have a copy of it. So if someone tries to cheat and change the score, everyone else can see that something’s wrong.

• Each page in the notebook is like a block, and every time you write down a new score, you add a new block.
• The notebook has lots of pages stuck together, this whole collection is called a chain, which is why it's called a blockchain.
• Everyone agrees on the rules before they start playing, these are like the rules of the game that keep everything fair.

If someone tries to change a score, all your copies need to agree on what the new score should be. That way, everyone stays in sync and no one can cheat without being caught!