What is Nmap? Nmap is free tool of network and vulnerability scanning.Network administrators use Nmap to discover how many and which device is connecting in network. It is also use for port scanning. Though Nmap has evolved over the years and is extremely flexible, at heart it's a port-scan tool, gathering information by sending raw packets to system ports. It listens for responses and determines whether ports are open, closed or filtered in some way by, for example, a firewall. Other terms used for port scanning include port discovery or enumeration. How it's works? Basically,Nmap is a port-scan tool, gathering information by sending raw packets to system ports. It listens for responses and determines whether ports are open, closed or filtered in some way by, for example, a firewall. Other terms used for port...