Windows IoT Core (or Windows Internet of Things) is a specialty version of Windows 10 for embedded devices like Raspberry Pi 2, Raspberry Pi 3 and MinnowBoard Max. It is a platform for the .Net developers to work on Internet of Things using Microsoft's technologies.
The Internet of Things (IoT) brings together devices, sensors, cloud, data and your imagination.
Windows 10 IoT Core brings the power of Windows to your device and makes it easy to integrate richer experiences with your devices such as natural user interfaces, searching online storage and cloud-based services.
The information of Windows IoT can be found in https://dev.windows.com/en-us/iot