A port scan helps you determine the ports that are open, listening, or closed on a network. Administrators use this to test network security and the system’s firewall strength. For hackers, it is a popular reconnaissance tool to identify the weak point to break into a system.
Some of the common basic port scanning techniques are:
UDP
Ping scan
TCP connect
TCP half-open
Stealth scanning
Check out this interesting blog on Ethical Hacking Tools now!