The UWP (Universal Windows Platform) is a unified platform for building and running apps on Windows 10 and Windows 10 Mobile.
UWP is the evolution of earlier technologies. So, with the release of Windows 8, a new architectural platform for applications was introduced - Windows Runtime (WinRT), which allowed running applications in the so-called Modern (Metro) mode on desktops and tablets. Then, with the release of Windows 8.1 and Windows Phone 8.1, this technology was developed - there were "universal applications" that could run immediately Windows 8.1 and WP8.1. And in July 2015, the new Windows 10 OS was officially released. It uses the UWP platform, which is an evolution of the Windows Runtime.
As the name of the platform suggests, it is universal - universal for all devices in the Windows 10 ecosystem. And these are ordinary destops, tablets, mobile devices, IoT (Internet of Things) devices, Xbox, Surface Hub devices. And a UWP app can work the same on all of these platforms as long as they have Windows 10 installed.
UWP coding has a number of benefits:
Sperad width. Currently Windows 10 is already installed on more than 400 million devices. On desktops, Windows 10 has already outpaced Windows 8/8.1.
Support for a wide range of devices . Desktops, tablets, smartphones, large Surface Hub tablets, various IoT devices, and in the future, HoloLens virtual reality devices - the range of devices on which Windows 10 can run is really wide.
App store and ease of distribution... The Windows Store is a great place to distribute UWP apps, both free and paid. The very capabilities of the platform and the Windows Store allow you to use different methods of monetization. For example, you can integrate blocks for displaying ads into applications through various SDKs. It can be distributed for a fee, and the payment can be flexibly configured. If necessary, you can build in the provision of a trial version, after using which the user can decide whether to buy the application or not. And you can also monetize using the freemium model, in which the application is shareware, and certain services within the application are provided for a fee. Moreover, all these monetization opportunities are provided by built-in SDK tools.
Rich platform capabilities . The UWP inherits a lot from the Windows Runtime of Windows 8.1 and at the same time brings many new features like richer cloud integration, Cortana, Win10's notification system, and more.
What you need to develop for UWP
Windows 10 is required for UWP programming. All other operating systems like Windows 8.1/8/7, let alone Windows XP, are not suitable!