Windows PE

Short for Windows Preinstall Environment, WinPE or Windows PE is a limited Win32 or Win64 operating system that helps boot a computer with no operating system. Windows PE gives the computer NTFS file system, network, script, and 32-bit or 64-bit driver support. A bootable Windows PE drive or disc can be created by downloading and installing the Windows AIK (WAIK).

Also see: Operating System definitions, UBCD, WAIK