Scanning ports and web servers using Nmap

Nmap is a prominent and widely used tool for scanning websites, networks, devices, and servers (such as HTTP, SSH, and SMTP) to identify open ports.

To try out the tool, download it from the official website by searching for "Nmap download." Once downloaded, install it just as you would any other program. Then, open a command-line interface—such as cmd or PowerShell—and enter the following command:

1/ `nmap --version`

This will display the tool's version. Next, enter the following command, replacing "example.com" with your target domain:

2/ `nmap example.com`

The scan results will appear, with the following terms indicating specific details:

PORT → Port number. STATE → Port status (e.g., open or closed). SERVICE → The service associated with the port.

Port 22 — SSH Typically used for connecting to and remotely managing a server via SSH.

Port 80 — HTTP The HTTP port; used for unencrypted web connections.

Port 443 — HTTPS

Used to access websites via HTTPS, which is an encrypted connection between the browser and the server.

Port 113 — Ident: If shown as open or closed, it indicates whether the service is currently active. Sometimes a question mark appears, meaning the tool is uncertain about the status (e.g., `5060/tcp open sip?` indicates uncertainty).

This is a basic overview. You can also use another command to scan all TCP (Transmission Control Protocol) ports and SSH servers:

1/ `nmap -sV -p- --reason example.com`

This explanation is for educational purposes only. I assume no responsibility for any illegal or unauthorized use. The explanation can be applied only to what pertains to you.