Ping scanning is a network discovery technique used to identify active devices on a network. It works by sending Internet Control Message Protocol (ICMP) echo request packets to a range of IP addresses. If a device is active and reachable, it responds with an echo reply, indicating that it is online. This method is often employed by network administrators to assess network health or by security professionals to map out potential vulnerabilities. While effective, ping scanning can be limited by firewalls or security settings that block ICMP traffic, making some devices undetectable.