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so one of the most important things about crypto is the blockchain.

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this is the fundamental technology that runs cryptocurrency.

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it's the idea behind making cryptocurrency stable, how people can actually trust it, trade with it, and own a piece of that cryptocurrency or the claim to that cryptocurrency on the blockchain.

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so in this video, we're going to talk about the basics of blockchain.

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this is not going to get incredibly technically deep because this course is really about crypto and security in the dark web, not crypto on its own.

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if you want to understand more about the deeper technologies and the math and algorithms and cryptography behind a blockchain, there are definitely other courses out there.

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if you would like it through dark web academy, definitely let us know and we might be open to exploring a course like that.

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so to dive into the fundamentals, a blockchain is really a chain of blocks.

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now these blocks and chains are not physical things.

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they're a logical representation of numbers on the internet.

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each block is really a set of different variables.

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so you have a hash, you have the transactions within that block, and then you have the previous hash of the block before it.

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so this is what chains the blocks together.

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it's because each block says, hey, the previous hash of the block before me was this.

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and at the end or the beginning of that block is the new hash of that block once it's completed.

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so that is how you get these chains blocks where you can work backwards, you can look at any block in the chain and you'll see its hash, which means you can find the next one because it'll have it in the next block.

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and you can look at the previous block and see its hash, and that'll be represented in the current block you're looking at.

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so the purpose of a blockchain is really to act as a ledger.

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it's a source of all the transactions that have ever happened on a cryptocurrency.

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take bitcoin, for example, you can see from now until the beginning of bitcoin, every transaction that has ever happened.

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you can see who sent money to who.

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you can see what money is sitting in a wallet unused.

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you can see all of the transactions and infer off of that data.

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so what type of data is actually stored in a block?

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well, let's say you have a wallet with this id.

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this is your wallet id.

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and they're claiming they have 35 bitcoin in their balance and they want to send all of it to a new wallet with that id, the 24 h 24. this is a transaction.

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this is a transaction that's going to end up in the new block on the blockchain.

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well, in order for that transaction to be put into that block, it has to be accepted by the network.

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in order for all of these transactions to build up, they have to be valid transactions.

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so it is sent into the block and all of these blocks are linked together, which is why you can see all of the transaction history.

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that wallet we just saw claimed it was sending this 35 bitcoin in that block.

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so later, if that wallet said it claims to send 35 more bitcoin, if it didn't receive bitcoin after this transaction, then it wouldn't have enough and the network would deny it.

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and we'll dive more into how that actually works in the next few videos.

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but that at a high level is how blockchains function.

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they really are just a bundling of transactions, every transaction possible, so you know what is happening.

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so we'll continue to build on this idea of the blockchain in the next few videos as we learn from a technical standpoint how all of this functions.

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you're probably very confused right now.

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you know, we just keep throwing out the word blockchain and you don't get it, but we'll start building on this fundamentally within this module to really give you a good base understanding of what cryptocurrency is and how it functions.