Original subtitles

When was the last time you bought a brand name item? Like a pair of sunglasses? Or a luxury watch?

How could you tell that it was the real thing, and not a knockoff?

Or let's say you wanted to make an investment in a multimillion dollar work of art like a painting? Or

a sculpture?

How could you guarantee that that work of art was actually done by the artist they claim? Or that it

wasn't stolen?

Having accurate information and a way to verify the sources of things when you're dealing in a situation

of a transaction of value is essential.

You need to have reliable systems that you can trust, which are tamper-proof.

But in a world where we're dealing with Internet fraud you're dealing with malware, you're dealing with

hacks of major institutions like banks or organizations or Internet service providers are getting cyber

hacked.

How can you trust the quality and integrity of the information that you're getting?

The answer is in a technology called blockchain, and blockchain can provide a single source of truth

that's verifiable, tamper-proof and unchangeable.

And that is what we're going to be talking about now.

What is a blockchain?

Let's begin with a simple definition of what a blockchain is. A block chain is a constantly growing

ledger that keeps a permanent record of all the transactions that have taken place, in a secure, chronological,

and immutable way.

Let's break down that definition into its individual elements so you can understand what it means.

For starters, a blockchain is a ledger.

It's a file, that's all it really is, it's a file that's constantly growing. So it keeps track of all the

transactions, in a permanent way. Which means once a transaction goes in, you can't pull it out. It’s permanently

in there.

That information is placed in there in a secure way.

It uses very advanced cryptography to make sure that it's actually locked inside the blockchain. The process,

every transaction, gets placed in chronologically so every transaction that happens, happens after the

previous one.

And finally, it's all immutable which means as you build that all these transactions onto the blockchain,

this ledger can never be changed.

That's what immutable means.