The Full Form of PXE is‍ Preboot eXecution Environment.

The Preboot Execution Environment (PXE) is an industry standard client/server interface that allows networked computers that are not yet loaded with an operating system to be configured and booted remotely by an administrator.

In computing, the Preboot eXecution Environment (PXE, most often pronounced as /ˈpɪksiː/ pixie) specification describes a standardized client-server environment that boots a software assembly, retrieved from a network, on PXE-enabled clients. On the client side it requires only a PXE-capable network interface controller (NIC), and uses a small set of industry-standard network protocols such as DHCP and TFTP.

The concept behind the PXE originated in the early days of protocols like BOOTP/DHCP/TFTP, and as of 2015 it forms part of the Unified Extensible Firmware Interface (UEFI) standard. In modern data centers, PXE is the most frequent choice for operating system booting, installation and deployment.