Explain the mining process with a practical example of how miners compete to add blocks.

Mining is the process where computers compete to solve mathematical puzzles to validate transactions and secure the blockchain network.\n\n**Mining Process Step-by-Step:**\n\n**Step 1: Collect Transactions**\nMempool (pending transactions):\n- Alice → Bob: 2 BTC\n- Charlie → Dave: 1.5 BTC \n- Eve → Frank: 0.8 BTC\n- Total fees: 0.05 BTC\n\n**Step 2: Create Block Header**\nBlock Header:\n{\n "previousHash": "0000a1b2c3d4e5f6...",\n "merkleRoot": "abc123def456...",\n "timestamp": 1640995200,\n "difficulty": "0000000000000000001a...",\n "nonce": 0\n}\n\n**Step 3: Mining Competition**\nTarget: Hash must start with 19 zeros\nMiners try different nonce values:\n\nMiner A tries nonce = 1:\nSHA256(blockHeader) = 1a2b3c4d... ❌ (does not start with enough zeros)\n\nMiner A tries nonce = 2:\nSHA256(blockHeader) = 9f8e7d6c... ❌\n\nMiner B tries nonce = 1,847,293:\nSHA256(blockHeader) = 0000000000000000001abc... ✅ WINNER!\n\n**Step 4: Broadcast Solution**\nWinning miner broadcasts:\n- Valid block with correct nonce\n- Network verifies solution\n- Block added to blockchain\n- Miner receives reward: 6.25 BTC + 0.05 BTC fees\n\n**Why Mining is Necessary:**\n\n**1. Security:**\n- Makes network attack expensive (need 51% of computing power)\n- Cost to attack > potential profit\n\n**2. Decentralization:**\n- No central authority decides which transactions are valid\n- Distributed consensus through competition\n\n**3. Incentivization:**\n- Miners earn rewards for maintaining network\n- Economic incentive ensures network operation\n\n**4. Fair Distribution:**\n- New coins distributed through work, not favoritism\n- Anyone can participate with computing power\n\n**Mining Difficulty Adjustment:**\nEvery 2016 blocks (~2 weeks):\nif (actual_time < 2_weeks) {\n increase_difficulty() // blocks found too fast\n} else if (actual_time > 2_weeks) {\n decrease_difficulty() // blocks found too slow\n}\n\n**Energy Consumption Trade-off:**\nHigh energy use = High security. The electricity cost makes attacks economically unfeasible.