How does the SHA256 in Blockchain Work? Crytocurrency Course

This article How does the SHA256 in Blockchain Work? A Demo by Anders.com is a demonstration of how the blockchain works. Readers will be able to appreciate what it means to have the blockchain to be immutable.

Ever wondered how the blockchain works? When we say the blockchain is immutable, what does it really mean?

A simple google search shows that immutable means that ‘ unchanging over time or unable to be changed.’ Most people get that. They understand that blockchain is really awesome because it cannot be hacked or changed by any central body. But practically speaking, how does it work?

Anders Bosworth has a great demonstration of how it works. You can visit this link , his website to see a well-coded example he has kindly done for everyone to use.

We start off the example on the first block on the left.

Let’s say we key in some transactions in the first box.

And then we press ‘mine’ to get a nonce number that solves the equation.

In this case, the ‘mine’ is what miners do at a higher level – to find the right nonce to ‘solve’ the equation, which is the nonce that fits the hash. In this case, the miners have to compete to solve it, and the first person to get the nonce is the winner who wins the mining reward.

Let’s move to the second block, and key in some random transactions.

Notice, that the hash of the 2nd block is formulated by both the hash of the previous block and the transactions.

And then when you press mine on this 2nd block, a new nonce is formed.

Let’s add some transactions to the third block.

Now, instead of pressing mine, let’s move back to the first block and try to ‘change’ the transactions.

See what happens when you try to remove one transaction from the first block.

Everything goes red. Basically, becomes ‘unsolved’. This means that all the previous blocks were invalidated because you tried to change something in the past.

That’s why it’s called a blockchain… because one block is linked to the next by the Hash. And that’s what makes it immutable because it’s all linked. If you touched one block or changed something in one block that has been linked, the whole thing becomes invalid or broken.

Here’s a video demo done by Anders.com that will explain it just as well.