Windows Runtime

Windows Runtime (WinRT) is a platform-agnostic component and application architecture first introduced in Windows 8 and Windows Server 2012 in 2012. It is implemented in C++ and officially supports development in C++ (via C++/WinRT, C++/CX or WRL), Rust/WinRT, Python/WinRT, JavaScript-TypeScript, and the managed code languages C# and Visual Basic (.NET) (VB.NET).

WinRT is not a runtime in a traditional sense but rather a language-independent application binary interface based on COM to allow object-oriented APIs to be consumed from multiple languages, with services usually provided by a full-blown runtime, such as type activation.^[1] That is, WinRT is an "API delivery system". Apps using the Windows Runtime may run inside a sandboxed environment to allow greater security and stability and can natively support both x86 and ARM.^[2][3] WinRT components are designed with interoperability among multiple languages and APIs in mind, including native, managed and scripting languages. Built-in APIs provided by Windows which use the WinRT ABI are commonly known as WinRT APIs; however, anyone can use the WinRT ABI for their own APIs.