Web1 (1990s) was read-only static websites. Web2 (2000s) brought user-generated content and social media - but ownership and data stayed with big tech platforms.

Web3 shifts power back to users through:

• Decentralisation: No single company controls the network
• Ownership: You own your data, identity, and digital assets
• Permissionless: Anyone can participate without approval
• Trustless: Code enforces rules, not middlemen

A blockchain is a distributed, immutable ledger. Think of it as a Google Doc that everyone can view, no one can edit retroactively, and updates require consensus from the network.

Key concepts:

| Concept | Meaning | |---|---| | Block | A batch of verified transactions | | Chain | Blocks linked cryptographically | | Node | A computer running blockchain software | | Consensus | How nodes agree on valid blocks | | Gas / Fees | Cost to process transactions |

Digital money native to a blockchain. Common examples:

• BTC (Bitcoin): The first cryptocurrency - digital gold and a store of value
• ETH (Ether): Native token of Ethereum, used for gas fees and staking
• USDC / USDT: Stablecoins pegged to the US dollar (1 token = $1)

A crypto wallet stores your private keys - not your coins. Your assets live on the blockchain; the wallet is how you access them.

Types of wallets:

| Type | Examples | Best For | |---|---|---| | Browser Extension | MetaMask, Rabby | Everyday DeFi and dApp use | | Mobile | Trust Wallet, Phantom | On-the-go access | | Hardware | Ledger, Trezor | Long-term cold storage | | Paper | Physical key backup | Ultra-secure backup |

NOTE

Security Rule #1: Never share your seed phrase with anyone. Anyone with your seed phrase has full control of your assets.

1. Go to metamask.io
2. Install the browser extension (Chrome, Firefox, Brave, or Edge)
3. Click "Create a new wallet"

MetaMask generates a 12-word seed phrase. This is your master backup key.

• Write it down on paper (do not screenshot or store online)
• Store it somewhere safe and offline
• Never type it into any website

• Buy ETH from an exchange (Coinbase, Binance, Kraken)
• Withdraw to your MetaMask wallet address (starts with

  0x...

  )
• You now have funds to use dApps

Smart contracts are self-executing programs stored on the blockchain. They automatically enforce rules without human intervention.

Example: A lending smart contract that:

1. Accepts your USDC as collateral
2. Lends you ETH automatically
3. Liquidates your position if collateral value drops too low

Everything is handled by code - no paperwork, no bank, no approval process.

Decentralised applications (dApps) are apps built on smart contracts. They look like regular websites but connect to the blockchain through your wallet.

Popular dApps:

| Category | Examples | |---|---| | DEX (Exchange) | Uniswap, Jupiter | | Lending | Aave, Compound | | NFT Marketplace | OpenSea, Magic Eden | | Social | Lens Protocol, Farcaster | | Gaming | Axie Infinity, Gods Unchained |

1. Set up a wallet and secure your seed phrase
2. Buy a small amount of ETH to cover gas fees
3. Try a simple swap on Uniswap (ETH to USDC)
4. Explore lending by depositing on Aave
5. Read project docs before investing in any token
6. Join communities on Discord and X/Twitter

NOTE

Golden Rule: Never invest more than you can afford to lose. Crypto is volatile. Start small, learn, then scale.

| Term | Definition | |---|---| | HODL | Hold on for dear life - don't sell | | DYOR | Do your own research | | Gas | Transaction fee on Ethereum | | Airdrop | Free tokens sent to early users | | Rug pull | Scam where developers steal funds | | DeFi | Decentralised Finance | | NFT | Non-fungible token - unique digital item | | DAO | Decentralised Autonomous Organisation |

Welcome to Web3. Take your time, stay curious, and never stop learning.