The document traces the history and evolution of network operating systems from 1951 to the present. Some of the key developments included J. Lyons and Company using technology to help their systems in 1951, the development of IBM's IBSYS in 1960, the introduction of Unix in 1969, the releases of DOS-11 in 1970 and Version 7 Unix in 1979, and the launches of Windows 1.0 in 1985, Linux 0.1 in 1991, Windows 95 in 1995, Windows Vista in 2006, Windows 7 in 2009, Windows 10 in 2015, iOS 14 in 2020, and Android 11 in 2020. The document provides an overview of the major operating systems across different decades from the 1950s to today.