If there’s one tool you absolutely need to know in cybersecurity, it’s Nmap (Network Mapper). It’s the Swiss Army knife of network scanning – free, open-source, and used by professionals everywhere.

Nmap can discover hosts on a network, identify open ports, detect what services are running, fingerprint operating systems, and even run vulnerability checks through its scripting engine. Let’s break it down.

Basic Nmap Scans

At its simplest, you give Nmap a target and it tells you what’s open:

nmap 10.0.6.200

That runs a basic scan against the top 1000 most common ports. But in the real world, you’ll want more control. Here are the flags you’ll use most often:

-sS – SYN scan (stealth scan). Sends a SYN packet and waits for a response without completing the TCP handshake. Fast and relatively quiet.

Part of the free Intro to Cyber course by Cover6 Solutions.