Docker provides several networking modes.
Bridge (default): Docker creates a Linux bridge. Containers get private IPs. NAT translates for external access.
Host: Container shares host network namespace. No isolation. Best performance.
None: No networking. Completely isolated.
Overlay: Containers on different hosts communicate over tunnels. Docker Swarm creates these.
Macvlan: Container gets its own MAC on physical network. Appears as a physical device. Useful for direct external access.