This Solidity tutorial is based on: https://www.youtube.com/watch?v=gyMwXuJrbJQ&t=102745s (Patrick Collins Course👍)
- Extensions
(2025.9.13)
- Some hackathons: chainlink, global, Dev folio
- Smart Contract
- Different between Bitcoin and Etherium protocol
- Oracle Problem
- Use decentralized oracle to build decentralized blockchain
- On-chain decentralized logic with off-chain decentralized data and computation called hybrid smart contracts
- Use "Smart Contract Platform" and "Blockchain" interchangeably
- Chainlink: the most polular and powerful decentralized Oracle network
- Dapp = Decentralized Application (Combination of smart contract) = Decentralized Protocol = Smart Contract
- Web 1, Web2, Web3
- (❓) censorship / decentralized censorship (16:54)
- Main purpose: Trust minimized agreements
Nearly everything in life is the result of an agreement or a contract (19:09). Smart Contract will solve society's critical trust issues (28:05)
- Decentralized Exchange
- DeFi
(2025.10.9)
- DAOs
- NFTs
- Transaction in test Ethereum chain
- Mnemonic
- Private Key
Test Phrase
- prize
- modify
- frown
- ethics
- hammer
- dress
- employ
- sick
- shield
- indoor
- brand
- useless
- Rinkeby is the most popular test network (Be sure to follow the last update in Github repository) (It is stopped currently.)
- Sepolia test network: https://sepolia.etherscan.io/
- Faucet
-
Transaction interpret
- hash
- status
- block
- timestamp
- from / to
- value
- transaction fee
- gas price / gas limit / usage by Txn / gas fees (Base, Max, Max Priority) / burnt
(gas is a unit of computational measurement. The more complex your transaction, the more gas you have to pay.) (gas prive × gas usage = transaction fee) (Ether and Gwei converter: https://eth-converter.com/)
(Extension: Can ETH Become DEFLATIONARY? EIP 1559 Explained - YouTube)
- Blockchain demo: Blockchain Demo
- SHA256 Hash
- Genesis Block (the first block in a blockchain)
- Mining
- Block
- Nonce: a bumber used to find the solution of the blockchain
- Private Key & Public Key (Blockchain Demo: Public / Private Keys & Signing)
- Signature
(2025.10.17)
- Consensus
- Chain Selection
- Sybil Resistance: such as PoW (Miner), PoS (Validator)
PoS nodes put up (stake) some collateral that they're going to behave honestly.
- ETH (PoW), ETH 2.0 (PoS)
- Block time
- Sybil Attack
- 51% Attack (Reference: ETH Classic and ETH)
- Nakamoto consensus: PoW and longest chain rule
- Transaction fee + block reward
- Block confirmations
- Randomness is important in blockchain
- Scalability (lack of blockchain space and high gas fee)
- ❓Sharding (a solution to solve scalability problem)
- Layer 1: Base layer blockchain implementation (such as BTC, ETH)
- Layer 2: Any application built on top of a layer 2 (such as chainlink, arbitrage, optimism)
- ❓ Rollups: Some layser 2 (such as arbitrage) roll up their transactions into a layer on like ETH
- Side chains: It is different from rollups. Their derive their security from their own protocols instead of base layers.
- Remix: https://remix.ethereum.org/
- Solidity Doc: https://docs.soliditylang.org/en/v0.8.30/