• Windows 8 and Its Impact: Windows 8 is a revolution for both desktop and tablet users with a new tablet-friendly UI. It brings substantial UI changes and extensive OS changes. Some initial word choices worried developers, but Microsoft's BUILD conference confirmed and exceeded expectations.
• WinRT and Windows RT: WinRT is short for Windows Runtime. "RT" in WinRT stands for "Runtime," while in Windows RT, it officially stands for nothing. Windows RT is a locked-down platform supporting only WinRT apps through the Windows Store. WinRT is the foundation for Windows apps and can run WinRT apps on Windows 8.
• A Brief History of Windows: Windows started with "windows" and basic APIs. OLE enabled compound documents in 1990, leading to COM in 1991. COM defines software components with interfaces and reference counting. It's language agnostic and has an ABI. Windows grew with new APIs like Win32, DirectX, and Media Foundation.
• COM's Complexity and Competition: COM is complex but solves complex problems. It faced challenges as only C++ supported all its capabilities. Java emerged as an alternative with features like garbage collection and multi-threading. Microsoft responded with.NET, which replicated COM features but also added new elements.
• .NET and Its Reception:.NET was developed as a response to Java. It had a C# language, a.NET Framework library, and an IL runtime. It was successful in the enterprise but less so in desktop applications. Different languages in.NET have different capabilities.
• The Averted Revolution (Longhorn): Longhorn was planned to be a radical change with WinFX, but it faced many challenges and was eventually scaled back to Windows Vista. Vista had some Longhorn elements but remained a native code OS.
• The Necessity of Change: Windows 7 was successful but still had issues. Longhorn's plans aimed to address these by improving GUIs (Avalon/WPF) and security/productivity (.NET). However, the Longhorn vision led to a split developer community.
• Split Developer Communities: The Longhorn vision divided developers..NET appealed to in-house LOB app developers, while native code developers stuck with Win32. Microsoft's divisions catered to different communities with little overlap. The creation of user interfaces was an area of common need.
• The Indomitable iPad and WinRT: The tablet revolution forced Windows to address touch UI. WinRT was introduced as the API for Metro-style apps. It's built on COM with some twists like IInspectable and uses.NET metadata.
• COM in the 21st Century: The new COM is better than the old one, especially for JavaScript developers. C++/CX simplifies WinRT programming for C++ developers.
• A New Face for Win32: WinRT is built on top of Win32, not an alternative. Metro-style apps use both WinRT and some Win32 APIs. This design has implications for compatibility and maintenance.
• What's in the Box (WinRT): WinRT is for Metro-style tablet apps, focusing on fast and fluid UI. It borrows from WPF and Silverlight but has some differences. It addresses the "don't block the input thread" issue with asynchronous I/O and thread pools.
• Sandboxing and the App Model: WinRT apps run in sandboxes with limited access and communication. Contracts and extensions are used for inter-app communication. Desktop apps have limited access to WinRT features.
• An Evolutionary Revolution: WinRT combines old and new ideas. It's positioned as a new Windows subsystem but is actually a modernization of Win32. It's a calculated risk with potential for extension or repositioning.