Mark Zbikowski

Mark Zbikowski
Born (1956-03-21) March 21, 1956 (age 68)
Detroit, Michigan
NationalityAmerican
Alma materHarvard University
Yale University
Known forDOS MZ executable
Work at Microsoft

Mark "Zibo" Joseph Zbikowski (born March 21, 1956) is a former Microsoft Architect and an early computer hacker. He started working at the company only a few years after its inception, leading efforts in MS-DOS, OS/2, Cairo and Windows NT. In 2006, he was honored for 25 years of service with the company, the third employee to reach this milestone, after Bill Gates and Steve Ballmer. He retired the same year from Microsoft.

He was the designer of the MS-DOS executable file format, and the headers of that file format start with his initials: the ASCII characters 'MZ' (0x4D, 0x5A).[1]

  1. ^ Inside Windows: An In-Depth Look into the Win32 Portable Executable File Format – MSDN Magazine, February 2002. "Every PE file begins with a small MS-DOS executable. ... The first bytes of a PE file begin with the traditional MS-DOS header, called an IMAGE_DOS_HEADER. The only two values of any importance are e_magic and e_lfanew. ... The e_magic field (a WORD) needs to be set to the value 0x5A4D. ... In ASCII representation, 0x5A4D is MZ, the initials of Mark Zbikowski, one of the original architects of MS-DOS."