Portable Executable Format (PE) [ Papers documenting the structure and make-up of the PE format… ]

This specification describes the structure of executable (image) files and object files under the Windows family of operating systems. These files are referred to as Portable Executable (PE) and Common Object File Format (COFF) files, respectively.

http://www.microsoft.com/whdc/system/platform/firmware/PECOFF.mspx