Software

Operating systems are very complex

Numbers of lines of code in operating systems:

Windows 95	11 million
Windows 98	18 million
Windows NT	4 million	(1993)
	28 million	(1998)
Windows 2000	35 million
Windows XP	40 million

Numbers of lines of code in operating-system kernels:

Linux	>2.5 million
Windows XP	>5 million

Windows 98 is said to have about 18 million lines of code (see transcript from Microsoft trial, 1999 Feb 2), up from about 11 million in Windows 95 (from posting by M.B. Trausch on linux-kernel list, 1999 Jun 21).

Windows NT is estimated to have grown from about 4 million lines of code in 1993 to about 28 million in 1998 (ref. graph in Windows NT 5.0 A Brief Look at the Future of NT by W.F. Slater, 1998).

Windows 2000 is said to have ‘29 million lines of new code’ (TCP, 2000 Apr, Exploring Windows 2000), with a total of maybe 35 million (ref. Windows 2000 beta bothers by Scott Berinato, 1999 Feb 5), depending on how they're counted.

Windows XP is said to have about 40 million lines of code (IEEE Spectrum, 2005 Sep, p. 41).

Linux kernel has "more than 2.5 million" and Windows XP kernel is "more than twice as large" (Computer, 2006 May, p. 44).

Slide show generated from sw.html by Weasel 2007 Mar 15