What is a blockchain?
What is a blockchain?
This is question and it’s answer are the most important building block of your understanding of blockchain and cryptocurrency.
It will open your eyes to the beauty and simplicity of the blockchain and cryptography.
The definition of a blockchain
A blockchain is a computer digital record, of all transactions on a blockchain from its very first transaction to the-most recent transactions. The computer ”blocks” are the equivalent of pages in a paper ledger. These blocks fill up, like a page fills up, and are bound together like the pages of a ledger are bound together or like the links in a chain. So they are called blockchains.
The blocks are just like the pages of a ledger in that they are arranged by date, the earliest transactions first.
Every time someone downloads a copy of the blockchain and the software which makes it work; they are down loading a copy of a digital ledger, which is a record of every transaction ever made on that blockchain.
These copies of the ledger are downloaded all over the earth and whatever computer device downloads it, it is in constant communication with all the other computers running a copy of the ledge.
This system makes sure that every computer has a copy of the most urgent ledger, up to the most recent transaction on earth.
Why? Accuracy.
A blockchain ledger works like a shared diary.
Imagine your entry: Dear Diary today I gave my friend 5 Bitcoin and then sign the entry. Now it is permanently entered. And as soon as you sign it that diary entry is sent all over the world and recorded in every Shared Diary in the world.
Now imagine your diary treated you like a King, and your word was law. And as soon as you wrote something it happened.
So now that you wrote about sending 5 Bitcoin to your friend it happens. Then you signed it. Then in a few minutes 5 Bitcoin from your wallet is transferred. And in all the shared diaries all over the world this is recorded.
What if you thought you sent your friend 50 Bitcoin, but he calls you and says only 5 arrived. You might distrust yourself friend, but all you have to do is open your diary and it will be written right there; 5 Bitcoin. And everyone else can see it too.
That’s how the blockchain works. Once you sign the entry it happens. And it’s recorded forever on all these computers all over the world.
If you think about it, it’s amazingly simple, and amazingly accurate and most importantly amazingly resistant to tampering, forging, altering, etc..
It was invented by the government to hide military secrets from the enemy. It’s a science called cryptography. But it’s not used to keep secrets, instead the cryptography is used to make it so no one can alter the entries.
An amazing unintended use case.
The end…for now.
Good definition..