In the beginning
In the accelerated timescale of computing, a quarter of a century is a veritable epoch. Today, we spend most of our computing time manipulating graphical user interfaces comprising windows, icons and menus, using a mouse-driven pointer. This 'GUI/WIMP' epoch, which may soon draw to a close as more 'natural' interfaces are developed, began in the 1970s at Xerox's legendary Palo Alto Research Center (PARC). Pioneering computers like the Alto and the Star were developed here, and although these machines had little or no commercial impact, they heavily influenced both Apple and Microsoft — whose products most certainly did.
Windows — originally codenamed 'Interface Manager' — was announced by Bill Gates in 1983, but didn't ship until 20 November 1985 (a pattern of delay that was to recur periodically through the product's history). Its first incarnation was as a front end bolted onto Microsoft's existing command-line DOS operating system. Here's a quote from the Windows 1.0 press release (recently unearthed and made available online by Ray Ozzie:
"Microsoft Windows extends the features of the DOS operating system, yet is compatible with most existing applications that run under DOS. Windows lets users integrate tasks they perform with their computers by providing the ability to work with several programs at the same time and easily switch between them without having to quit and restart individual applicatications. In addition, it provides a rich foundation for a new generation of applications."
Windows 1.0, which could only support tiled (not overlapping) windows, included standard desktop features such as MS-DOS Executive (DOS file manager), Calendar, Cardfile, Notepad, Terminal, Calculator and Clock; utlilities including Control Panel, PIF (Program Information File) Editor, RAMDrive (for managing memory cards designed to beat the PC's 640KB memory limit), Clipboard and Print Spooler. There was even a game, Reversi. In a 'special introductory offer', Windows 1.0 came with Windows Write and Windows Paint and cost $99.
The minimum system requirements for Windows 1.0 now seem impossibly quaint: MS-DOS version 2.0; two double-sided floppy disk drives or a hard disk; 256KB of memory or greater; a graphics adapter card.
Vista, codenamed Longhorn, was a much-delayed attempt to supersede 2001's successful Windows XP, and was criticised for failings in many areas — exacting hardware requirements, lack of legacy application compatibility, patchy driver support, long boot times, poor performance, security holes, over-zealous user access control, to name but several.
Windows 7, eight years after the release of XP and three years after Vista finally shipped in November 2006, put most of that right. To quote our review at the time: "By fixing most of the perceived and real problems in Vista, Microsoft has laid the groundwork for the future direction of Windows".
Windows 7, which comes in six editions (Starter, Home Basic, Home Premium, Professional, Enterprise and Ultimate), is undoubtedly a success: in its Q4 2010 earnings report, Microsoft claimed that it had sold 175 million copies in the nine months since launch — an average of 640,000 copies a day. Certainly, many businesses that held off upgrading from XP to Vista are now seriously considering the move to Windows 7.
Windows 7's system requirements make an interesting comparison to those for Windows 1.0: 1GHz or faster 32-bit (x86) or 64-bit (x64) processor; 1GB (32-bit) or 2GB of RAM (64-bit); 16GB of available hard disk space (32-bit) or 20GB (64-bit); DirectX 9 graphics device with WDDM 1.0 or higher driver. The server version of Windows 7 is Windows 2008 R2, which is 64-bit only.
Windows through the years
We have neither the time, nor indeed the will, to document every version of Windows that Microsoft has delivered over the past 25 years. However, in this chart we've tried to capture a flavour of the operating system's evolution. For all the family-history detail you can handle, check out this comprehensive diagram from developer Éric Lévénez.
The green portion of the chart bars marks the period the Windows version was actively updated, while the amber part covers the time it was officially supported by Microsoft. Here's a whistle-stop tour of some key landmarks.
Windows 2.0 (1987) added overlapping windows and PIFs (Program Information Files) that told Windows how to run DOS applications. Windows 3.0 (1990) exploited Intel's 286 and 386 processors better, introduced Program Manager and File Manager, and delivered enhanced colour support. Windows 3.1 (1992) added scalable fonts, with integrated networking following swiftly in the Windows for Workgroups versions. Windows NT 3.1 (1993) marked a break with the past, being a brand-new, fully 32-bit, OS aimed at the business market. Windows 95 launched to huge fanfare on 24 August 1995, delivering a hybrid 32-bit/16-bit OS with a new GUI including the first appearance of the Start button and taskbar. Windows 95's lineage continued through Windows 98 and the ill-starred Windows ME (2000).
Meanwhile, in the business space, Windows 2000 succeeded NT 4.0, introducing many Windows 98-style features including plug-and-play. Setting a pattern for the future, Windows 2000 came in several editions — Professional, Server, Advanced Server and Datacenter Server (versions were also available for Intel's 64-bit Itanium processor). Support for Windows 2000 only ended in July this year. Windows XP (2001) succeeded Windows 2000 and Windows ME on the consumer/business desktop: fully NT-based, XP came in Home, Professional, 64-bit, Media Center, Tablet PC and embedded editions, and has proven one of Microsoft's most successful and longest-lasting Windows versions. Among its key new features was 802.1x networking support and Remote Assistance. Support for XP will not finally end until April 2014.
Security and an updated graphical interface (Aero) were the main preoccupations of 2006's Windows Vista. However, as mentioned earlier, history will not judge this Windows release kindly. It also came in an array of editions: Starter, Home Basic, Home Premium, Business, Enterprise, Ultimate (all except Starter with 32-bit and 64-bit support). Windows 7 and Server 2008 R2, released in October 2009, bring us up to date.
Windows system requirements
Today's desktop computer is a far cry from that of five years ago, let alone a quarter of a century past. Each new version of Windows adds new functionality while having to support a multitude of legacy features, so it's no surprise to find that the minimum requirements for running the OS have escalated over the years. Even so, it's interesting to chart the minimum recommendations for processor speed, memory (RAM) and free hard disk space since 1995.
The unlabelled data points, reading from the left, are for Windows NT 3.51, Windows 95, Windows NT 4.0, Windows 98 and Windows ME.
Each successive version of Windows consumes ever more of Microsoft's programming and testing resources, and spews out millions more lines of code. These charts show how the development process unfolded between Windows NT 3.1 in July 1993 and Windows Server 2003 in April 2003 (data from knowing.net ). Like Server 2003, Windows Vista is reckoned to contain 50 million source lines of code; no estimate is available for Windows 7.