Technical Guide An explanation of each part of bitcoin. Node Memory Pool Candidate Block Mining Target Blockchain Longest Chain Chain Reorganisation 51% Attack blk.dat Block Block Header Merkle Root Bits Nonce Block Hash Transaction TXID Transaction Data Input Output scriptPubKey Locktime Fees Weight UTXO Coinbase Transaction Script P2PK P2PKH P2MS P2SH NULL DATA Keys Private Key WIF Private Key Public Key Public Key Hash Address Checksum Base58 ECDSA HD Wallets Mnemonic Seed (BIP 39) Extended Keys (BIP 32) Derivation Paths (BIP 44) Other Hash Function Hexadecimal Little-endian Magic Bytes VarInt VOUT