Which tool is used for network scanning and discovering devices on a network in Linux?

netstat displays network connections, routing tables, interface statistics, and masquerade connections, but is not primarily a network discovery or scanning tool.

tcpdump is a packet analyzer that captures and displays network packets, primarily used for network monitoring and troubleshooting, not active device discovery.

Nmap (Network Mapper) is an essential open-source utility for network exploration and security auditing, capable of discovering hosts, services, operating systems, and open ports on a network through various scanning techniques.

traceroute maps the path packets take to a network host, showing intermediate hops, but it does not perform broad network scanning or device discovery like Nmap.