Ports (port scanner)

What it does: checks which "doors" (ports) are open on a device — each open port is a service it's offering (web, SSH, mail, …). It answers "what is this machine running / exposing?" by trying a TCP connection to each port and listing the ones that accept it, with the usual service name. Same IPv4/IPv6/Auto picker as Ping/Trace.

What you need: a target host or IP. By default it checks a set of common ports; you can give it your own list/range.

Safe to run: only scan hosts you OWN or are authorized to test — port-scanning someone else's systems can violate policy or law. On your own gear it's harmless.

What to expect / reading results: "open" means something is actively listening there (443 = HTTPS, 22 = SSH, 80 = web, 3389 = Windows Remote Desktop, …). Closed/filtered ports simply don't answer. The thing to look for is an OPEN port you didn't expect on that device — that's a possible misconfiguration or an unwanted/rogue service.