Explain CAN bus protocol and its advantages in automotive applications.

CAN (Controller Area Network) is a robust serial bus for real-time distributed control. Features: Multi-master with message-based arbitration (lower ID = higher priority), differential signaling for noise immunity, built-in error detection (CRC, bit stuffing, acknowledgment), automatic retransmission, fault confinement (error counters isolate faulty nodes). Data frames contain: arbitration ID (11 or 29 bits), control, data (0-8 bytes), and CRC. Standard CAN runs at 1 Mbps; CAN-FD extends to 8 Mbps with 64-byte payloads. Dominant in automotive, industrial, and medical applications requiring reliability.