Nmap Target Selection
Scan a single IP nmap 192.168.1.1
Scan a host nmap [Only registered and activated users can see links. ]
Scan a range of IPs nmap 192.168.1.1-20
Scan a subnet nmap 192.168.1.0/24
Scan targets from a text file nmap -iL list-of-ips.txt

Nmap Port Selection
Scan a single Port nmap -p 22 192.168.1.1
Scan a range of ports nmap -p 1-100 192.168.1.1
Scan 100 most common ports (Fast) nmap -F 192.168.1.1
Scan all 65535 ports nmap -p- 192.168.1.1

Nmap Port Scan types
Scan using TCP connect nmap -sT 192.168.1.1
Scan using TCP SYN scan (default) nmap -sS 192.168.1.1
Scan UDP ports nmap -sU -p 123,161,162 192.168.1.1
Scan selected ports - ignore discovery nmap -Pn -F 192.168.1.1

Service and OS Detection
Detect OS and Services nmap -A 192.168.1.1
Standard service detection nmap -sV 192.168.1.1
More aggressive Service Detection nmap -sV --version-intensity 5 192.168.1.1
Lighter banner grabbing detection nmap -sV --version-intensity 0 192.168.1.1

Nmap Output Formats
Save default output to file nmap -oN outputfile.txt 192.168.1.1
Save results as XML nmap -oX outputfile.xml 192.168.1.1
Save results in a format for grep nmap -oG outputfile.txt 192.168.1.1
Save in all formats nmap -oA outputfile 192.168.1.1

Digging deeper with NSE Scripts

Scan using default safe scripts nmap -sV -sC 192.168.1.1
Get help for a script nmap --script-help=ssl-heartbleed
Scan using a specific NSE script nmap -sV -p 443 –script=ssl-heartbleed.nse 192.168.1.1
Scan with a set of scripts nmap -sV --script=smb* 192.168.1.1

HTTP Service Information
Gather page titles from HTTP services nmap --script=http-title 192.168.1.0/24
Get HTTP headers of web services nmap --script=http-headers 192.168.1.0/24
Find web apps from known paths nmap --script=http-enum 192.168.1.0/24