Bitcoin Core is the reference implementation of a Bitcoin full node. It connects to the Bitcoin peer-to-peer network to download and fully validate blocks and transactions according to consensus rules. The system includes a full node daemon (bitcoind), a command-line interface (bitcoin-cli), a graphical user interface (bitcoin-qt), and a set of utility tools (bitcoin-tx, bitcoin-wallet, bitcoin-util). The architecture is modular: a kernel library (libbitcoinkernel) encapsulates consensus-critical code, a node layer manages networking, mempool, and chainstate, a wallet subsystem handles key management and transaction signing, and an IPC layer supports multiprocess separation. External dependencies include LevelDB (storage), libsecp256k1 (elliptic curve cryptography), ZeroMQ (notifications), and Qt (GUI). The system exposes JSON-RPC and REST APIs for programmatic interaction, and supports advanced features like BIP324 encrypted P2P transport, compact block relay, assumeutxo snapshots, and descriptor-based wallets.