The -sP option in Nmap is used for host discovery without port scanning, which helps in identifying live hosts without triggering portscan alerts on IDS devices. It sends an ICMP echo request, a TCP SYN packet to port 443, a TCP ACK packet to port 80, and an ICMP timestamp request to each target IP address and waits for a response. Any responses are considered as indications of a live host. Reference:= Cisco Cybersecurity Operations Fundamentals - Module 5: Endpoint Threat Analysis and Computer Forensics