Why is Privacy important - Bitcoin?

Privacy is awesome but why do we care at all ? why cant we keep the data all public and the dangers of the applications without privacy on blockchains

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Lesson Transcript

  • [00:00 - 00:14] So this is a Bitcoin block explorer. And in here you can find out everything about the block, the transactions, the hash rate, and basically who was the miner, the size of the block, and everything else.

  • [00:15 - 00:25] So let's start by looking at the latest block. And in the latest block, you can see, first of all, the hash of the block, which is unique to the block, the confirmation.

  • [00:26 - 00:36] So that's basically the height that's currently being built after this block. So this is the confirmations that are used when you buy something.

  • [00:37 - 00:48] So if you go and buy something expensive, or sometimes even coffee, they will say that they will wait for six confirmations. That means there will be six blocks after this.

  • [00:49 - 00:56] And then they will accept that the transaction actually happened. So this is what we call a probabilistic finality.

  • [00:57 - 01:25] At any given point in time, we only have a probability that the transaction will not be reverted. So when there is only one confirmation, the probability that the transaction will not be reverted or the block will actually get orphaned is very high, which is why the recommended confirmations for Bitcoin is six or even 18 if it's a very high value transaction.

  • [01:26 - 01:33] So of course, there was a timestamp, there was the height, there was the minor for this one is unknown. It's just an address.

  • [01:34 - 01:45] We don't know where this is, but we can look at other blocks where this is known. And the things that we can actually look at are, for example, the fee reward and the block reward.

  • [01:46 - 02:00] This is what the minor gets for mining this block. So they earned 6.25 BTC, which is the current amount that minor gets for mining a block.

  • [02:01 - 02:10] And in transaction fees, they receive 0.177. And we can also go down further and start looking at the block transactions.

  • [02:11 - 02:22] So you can look at each individual transaction and see what's happening. And you can also see that there's confirmations.

  • [02:23 - 02:27] So you can go down. But this is basically what the block explorer is.

  • [02:28 - 02:40] We can actually go back and start looking at the minor like a few pool. And so miners are actually known and they also work in pools.

  • [02:41 - 02:52] So if you have some computing power, you can become a part of a pool and you get a fraction of this mining reward. And so they can confirm transactions.

  • [02:53 - 03:04] And you can see this is the amount of BTC that they have received over time. And you can again see different transactions.

  • [03:05 - 03:13] You can see that the coin basically nearly generated coins and a lot of other things. And you can go down into what the transaction does itself.

  • [03:14 - 03:27] And it will basically tell you what the inputs and the outputs are. So because Bitcoin is a UTXO based model, an Ethereum is an account based model.

  • [03:28 - 03:34] They both have their advantages and disadvantages. But it's out of scope for us to go too deep into that.

  • [03:35 - 03:45] But there is some really great resources out there if you would like to learn more. But you can go and explore around what these block explorers show you.

  • [03:46 - 03:56] You can trace different addresses. You can see how many transactions they have, how much BTC they own, and what their current balance is.

  • [03:57 - 04:04] You can of course send and receive as well. So you can, for example, see how much money is owned by a single address.

  • [04:05 - 04:14] And this is, again, just a public private key pair, which owns this. And of course, if someone could guess the private key correctly, they can get all this money.

  • [04:15 - 04:17] But it's almost impossible.

So this is a Bitcoin block explorer. And in here you can find out everything about the block, the transactions, the hash rate, and basically who was the miner, the size of the block, and everything else. So let's start by looking at the latest block. And in the latest block, you can see, first of all, the hash of the block, which is unique to the block, the confirmation. So that's basically the height that's currently being built after this block. So this is the confirmations that are used when you buy something. So if you go and buy something expensive, or sometimes even coffee, they will say that they will wait for six confirmations. That means there will be six blocks after this. And then they will accept that the transaction actually happened. So this is what we call a probabilistic finality. At any given point in time, we only have a probability that the transaction will not be reverted. So when there is only one confirmation, the probability that the transaction will not be reverted or the block will actually get orphaned is very high, which is why the recommended confirmations for Bitcoin is six or even 18 if it's a very high value transaction. So of course, there was a timestamp, there was the height, there was the minor for this one is unknown. It's just an address. We don't know where this is, but we can look at other blocks where this is known. And the things that we can actually look at are, for example, the fee reward and the block reward. This is what the minor gets for mining this block. So they earned 6.25 BTC, which is the current amount that minor gets for mining a block. And in transaction fees, they receive 0.177. And we can also go down further and start looking at the block transactions. So you can look at each individual transaction and see what's happening. And you can also see that there's confirmations. So you can go down. But this is basically what the block explorer is. We can actually go back and start looking at the minor like a few pool. And so miners are actually known and they also work in pools. So if you have some computing power, you can become a part of a pool and you get a fraction of this mining reward. And so they can confirm transactions. And you can see this is the amount of BTC that they have received over time. And you can again see different transactions. You can see that the coin basically nearly generated coins and a lot of other things. And you can go down into what the transaction does itself. And it will basically tell you what the inputs and the outputs are. So because Bitcoin is a UTXO based model, an Ethereum is an account based model. They both have their advantages and disadvantages. But it's out of scope for us to go too deep into that. But there is some really great resources out there if you would like to learn more. But you can go and explore around what these block explorers show you. You can trace different addresses. You can see how many transactions they have, how much BTC they own, and what their current balance is. You can of course send and receive as well. So you can, for example, see how much money is owned by a single address. And this is, again, just a public private key pair, which owns this. And of course, if someone could guess the private key correctly, they can get all this money. But it's almost impossible. [BLANK_AUDIO]