Even in just this introduction part, we've learned a ton, so let's do a quick summary of what we've learned so far. Bitcoin was the first protocol to take this blockchain technology into the limelight and take these cryptocurrencies into the mainstream. Bitcoin is a sort of digital gold or a store of value, able to make transactions between users in a decentralized manner. Ethereum and other smart contract platforms take this blockchain technology one step further, enabling people to make smart contracts and decentralize trust-minimized agreements. These smart contracts and decentralized applications can access and interact with the real world using something called decentralized oracle networks. Chainlink is a decentralized network that allows us to build these hybrid smart contracts, which combines our on-chain logic with our off-chain decentralized data and decentralized computation, giving rise to our logic being completely decentralized and our data and external computation being completely decentralized, giving us all the features that traditional agreements and traditional contracts have. Now, these digital currencies like Ethereum and Bitcoin have value even without the smart contract part, having a censorship-resistant decentralized store of value.

is measurably powerful in its own right. We have some links in the GitHub repository that'll teach you how this decentralized store of value flips traditional finance on its head, and it's another one of the great reasons for building smart contracts. But again, the easiest way to boil it down is trust-minimized agreements or unbreakable promises. But let's also go into some of these other features that smart contracts have over our traditional environment. The first feature, of course, is that they are decentralized and they have no centralized intermediary. The different individuals that run one of these blockchains are known as node operators, and it's the combination of all these thousands of node operators running the same software, running these algorithms, running these smart contracts that make the network decentralized. We'll dive deeper into how that works later. The next feature is transparency and flexibility in these decentralized networks. Since all these individual node operators run this software, everybody can see everything that's happening on-chain, meaning there's no shady deals.

there's no weird things happening. Anything that's going to be unfair, people will be able to see and just not use. Everybody has perfect information and has to play it by the same rules. Now, additionally, this doesn't mean that there's no privacy. The blockchain is pseudo-anonymous, meaning that you aren't necessarily tied to an identity in real life. They also have the feature of speed and efficiency. For those of you who have ever tried to do a bank transfer or send money across seas, you know it sometimes can take two to three weeks when in fact all these banks are really doing is basic math. They're subtracting money from your balance and adding it to some other balance. Why does it take so long? In the blockchain, all of these transactions happen instantly. Another instance for those in the financial world today know that clearinghouses and settlement days can take a long time. In the blockchain, there's no need for any of that because they happen instantly. This obviously is much quicker, but it also makes for much more efficient interactions with each other. Security

and immutability again. Immutable means that it can't be changed once a smart contract is deployed. That's it. Whatever is in the code is going to be in the code forever. They cannot be altered or tampered with in any way. This means that the security is much easier. Whereas in a centralized world, somebody can hack into the server, jump into the database, and change some numbers. You can't do that in the blockchain world. And since it's decentralized, in order to hack the blockchain, you'd have to take over half of the nodes, as opposed to in the centralized world where you only have to take over one. In the regular world, if your computer and your backup computer go down, all of your data is gone. In the blockchain world, if your computer and your backup computer go down, all your data is safe because it's being run on all these other decentralized nodes. And even if a few hundred nodes or if a few thousand nodes go down, it doesn't matter because as long as one node has a copy of the blockchain, you're good to go.

hacking a blockchain is nearly impossible and leaps and bounds more difficult than hacking a centralized server. Not only that, but this is safer in the asset sense as well. All you need to access your credentials and your information and your assets is your private key, which is basically your password for all of this. And as we've discussed in the video, these smart contracts remove this counterparty risk, remove this centralized intermediary, remove these trust gateways that we have to do in web 2. When we engage with users and individuals, they don't always have our best interests at heart. Smart contracts remove this counterparty risk because once one of these contracts is created, they can't go in and they can't alter it, and they can't let greed or ego or anything else get the better of them and alter the terms of the deal. And as we said, this gives rise to these trust-minimized agreements or these programmatic unbreakable promises. We move away from brand-based agreements to math-based agreements. We can look at the

cryptography. We can look right at the code and see exactly what something is going to do and how it's going to execute versus having to rely on a human being doing the right thing with smart contracts and decentralized hybrid smart contracts. Doing the right thing is infrastructural. All these pieces boil down to us having the freedom to interact the way we want to interact without having to be afraid that interacting like that is going to screw us over. This trust-minimized peace, these unbreakable promises, make interactions so much better. In the purely web 2 world, we're constantly bombarded with messages of projects and protocols pushing us to move or act in the direction that makes them more profitable versus in the smart contract space. We can see everything transparently, and we can even engage and interact and be partially owners of the protocols and the interactions that we decide that we want to be a part of. So smart contracts have been around for a few years now, and what have they generated for what industries have come about due to these smart contract.

platforms being around. Well, you've probably heard of some of these, and some of these we've already mentioned, but let's give you a quick refresher. DeFi, D5, stands for decentralized finance, and it gives users the ability to engage with finance and markets without having to go through a centralized intermediary. For example, like we said with Robinhood, you no longer have to trust that Robinhood would continue to give you access to the markets. You instead would be able to see in the smart contract, Yes, I have access to the markets. Or in the 2008 financial crisis, you never have to trust that these groups and institutions are giving you the correct things on the back end. You can see everything transparently right on the blockchain. You can engage with things like money markets and sophisticated financial products easily, effectively, and securely. If you're really excited about DeFi, we have a ton of DeFi examples showing you how to build and interact with these protocols in coming lessons. DAOs, or decentralized autonomous organizations, are another group that

we've already mentioned Dows are groups that are governed completely decentralized by a set of instructions or smart contracts on chain. There are some massive benefits here where engagement's much easier, the rules are black and white, and you can see everything directly on chain. Voting and governance technology is completely decentralized, and the blockchain space is one of the big ones pushing how we can evolve politics and how we can involve governance to make it more efficient, fair, and reasonable. And you better know it, we have some examples of how to build dowels and how to work with Dallas incoming lessons, so be sure to watch those. NFTs stand for non-fungible tokens and can really be kind or described as digital art or just a unique asset. It can do so much more, but we'll keep it high level for now. Projects like board apes and crypto punks have revolutionized the way that people get paid for their work, show off their creativity, status, and so much more. And yes, of course, we have lessons showing you how to create and interact

with NFTs as well. So many other groups and so many other industries are being created as a result of this insane technology. And maybe after finishing the journey with us here, you go out, and you'll be the one to pioneer the next industry or the next billion-dollar idea. You've learned so much already, but now that we've learned a lot of this high-level information, let's finally jump in, and let's make your first transaction, and let's get you set up to interact with this new world. In this next section, we're going to get you a wallet, and we're going to show you exactly what a transaction looks like and feels like. Let's dive in.

Lesson 1 Part 3  | Quick Recap - Solidity & Foundry Full Course

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