Explain blockchain technology with a simple example of how blocks are connected.

Blockchain is a distributed digital ledger that stores data in blocks linked together using cryptographic hashes.\n\n**Basic Structure:**\n\nBlock 1 (Genesis):\n- Data: "Alice sends 10 coins to Bob"\n- Hash: 0x1a2b3c...\n- Previous Hash: 0x000000...\n\nBlock 2:\n- Data: "Bob sends 5 coins to Charlie"\n- Hash: 0x4d5e6f...\n- Previous Hash: 0x1a2b3c... (Block 1 hash)\n\n**Key Properties:**\n• **Immutable** - Changing any block breaks the chain\n• **Decentralized** - No single point of control\n• **Transparent** - All transactions are visible\n• **Secure** - Cryptographically protected\n\n**Simple Example:**\nImagine a notebook shared among friends where:\n- Each page (block) contains transaction records\n- Every page references the previous page number (hash)\n- If someone tries to modify an old page, everyone notices because the page numbers do not match\n- Everyone has a copy, so no single person can cheat\n\nThis creates an unbreakable chain of records that everyone can trust without needing a central authority.