Explain cryptocurrency and its key differences from traditional digital payments.

Cryptocurrency is digital money that uses cryptography for security and operates on blockchain networks without central authority.\n\n**Traditional Digital Money (Bank Transfer):**\nAlice → Bank → Bob\n- Bank verifies Alice has $100\n- Bank deducts $100 from Alice\n- Bank adds $100 to Bob\n- Bank maintains central ledger\n\n**Cryptocurrency Transaction:**\nAlice → Blockchain Network → Bob\n- Alice signs transaction with private key\n- Network nodes verify signature and balance\n- Transaction added to blockchain\n- No central authority needed\n\n**Key Differences:**\n\n| Aspect | Traditional Digital | Cryptocurrency |\n|--------|-------------------|----------------|\n| Control | Central bank/authority | Decentralized network |\n| Verification | Bank validates | Network consensus |\n| Reversibility | Can be reversed | Irreversible |\n| Privacy | Bank knows all details | Pseudonymous |\n| Availability | Business hours | 24/7/365 |\n| Borders | Geographic restrictions | Global |\n| Fees | Bank fees | Network fees |\n\n**Example Cryptocurrencies:**\n• **Bitcoin (BTC)** - Digital gold, store of value\n• **Ethereum (ETH)** - Smart contract platform\n• **Litecoin (LTC)** - Faster Bitcoin alternative\n\n**Benefits:** No intermediaries, global access, programmable money, censorship resistance