When Microsoft announced that Windows 10 would be an Arduino Certified operating system, it wasn't entirely obvious what it meant by that. The Arduino platform has been compatible with Windows since its very first release, and while the company demonstrated that it would be possible to interface a Bluetooth-equipped Arduino microcontroller with a Windows Phone handset it was nothing makers hadn't been doing with third-party applications for years.
Now, though, the company's overall goals are more clear. Microsoft has officially announced that Arduino's Wiring syntax is now officially supported by Windows 10 Internet of Things (IoT) Core, its free maker-centric variant of the operating system. Originally built by Hernando Barragán in 2003 as an extension to Processing, Wiring was the language chosen for the Arduino project. When you're able to make an LED flash with a simple digitalWrite() instruction, you're using Wiring - and now it's possible to use the same code on Windows 10 IoT Core devices.
For Windows developers, this makes it easier to branch out into physical electronics projects: Arduino code should, in the main, run largely unmodified within Windows 10 IoT Core while other Windows-centric code can also be included. For Arduino users, this further extends the number of devices that can be addressed using the familiar Wiring syntax.
If you have a Windows 10 IoT Core compatible devices, you can get started by following the official instructions.
Arduino is one of the most popular platforms among makers. Its community has produced a large number of libraries to interface with peripherals such as LED displays, sensors, RFID readers and breakout boards. One of the main drivers for Arduino's adoption is its simplicity. With Windows 10 IoT Core, you can now create or port Arduino Wiring sketches that will run on supported IoT Core devices.