Explain the process of creating and verifying digital signatures with an example.

Digital signatures use public-key cryptography to prove transaction authenticity without revealing private keys.\n\n**Key Generation Process:**\n1. Generate random private key (256-bit number)\n Private Key: d = 0x1234567890abcdef...\n\n2. Calculate public key using elliptic curve\n Public Key: Q = d × G (where G is generator point)\n Q = (x, y) coordinates on curve\n\n3. Create wallet address from public key\n Address = Hash(Public Key)\n\n**Transaction Signing Process:**\nStep 1: Create transaction\ntx = {\n from: "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa",\n to: "1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2", \n amount: 0.5,\n fee: 0.001\n}\n\nStep 2: Hash transaction data\ntxHash = SHA256(tx) = 0xabc123...\n\nStep 3: Sign with private key\nsignature = sign(txHash, privateKey)\n\nStep 4: Broadcast transaction + signature\n\n**Verification Process:**\nStep 1: Receive transaction + signature\nStep 2: Hash transaction data\nStep 3: Verify signature using public key\nif (verify(signature, txHash, publicKey) == true) {\n transaction_valid = true\n} else {\n transaction_invalid = true\n}\n\n**Security Properties:**\n• **Authentication** - Proves sender identity\n• **Non-repudiation** - Sender cannot deny signing\n• **Integrity** - Detects any data tampering\n• **Unforgeable** - Cannot create valid signature without private key\n\n**Real-world Analogy:** Like a handwritten signature, but mathematically impossible to forge and can be verified by anyone.