Windows (operating system)
Windows is a series of operating systems produced and maintained by Microsoft Corporation. It was estimated that as of December 2007 Microsoft Windows accounted for nearly 90% of operating system usage, with 3 out of 4 being to the Windows XP. Windows is used both as a desktop operating system and a server operating system, and is intended for use with the Intel x86-64 family of processors.
Early versions of Windows (98 and earlier) were notoriously unreliable, despite (or maybe because of?) Microsoft's near-monopoly share of the operating system market. They crashed so often that the term "blue screen of death" entered the vocabulary. See also this satire: Matrix Runs on Windows XP