Microsoft Windows is without doubt one of the most popular Operating Systems known today. Used by a vast majority of people in homes and offices worldwide, Microsoft Windows is a proprietary (also known as 'closed source') Operating System from one of the world's largest software companies, Microsoft (MS).

The latest version of the Windows Operating System from Microsoft is Windows Vista. Windows Vista comes in sevral different versions, Vista Starter, Vista Home Basic, Vista Home Premium, Vista Ultimate, Vista Business, and Vista Enterprise.

MS Windows first became very popular in the early 1990s, when Microsoft launched Windows 3.1 and Windows 3.11 for Workgroups. At that time, MS Windows was an additional software that people installed on MS DOS (Disk Operating System).
Later, with MS Windows 95, you no longer had to install DOS. MS Windows 95 became a pure operating system. Later came MS Windows 98, and MS Windows ME (Millennium Edition). These versions were specifically targeted at client computers.
MS also introduced the Windows NT family of operating systems meant for servers and workstations. This family was followed by MS Windows 2000, which was based on MS Windows NT technology.

Microsoft then came up with Windows XP and the Windows 2003 server family. Windows XP was the first version that came in different editions (Home and Professional) with the Home edition targeted at home and small users, and the Professional edition aimed at office users, who wanted to connect to a Windows 2000 or Windows 2003 server network.

The latest version of the Microsoft Windows Operating System is Windows Vista.