PXE booting, or Preboot Execution Environment, is a method that allows a computer to boot up using a network connection instead of a local storage device like a hard drive. This process is useful for installing operating systems or running diagnostics on multiple machines without needing physical media. During PXE booting, the computer's firmware sends a request over the network to find a PXE server. The server then provides the necessary files to start the operating system, enabling the computer to load and run software directly from the network. This is particularly beneficial in enterprise environments for managing large numbers of devices.