Windows 10 is a series of personal computer operating systems produced by Microsoft as part of the Windows NT family of operating systems. It was released on July 29, 2015. Windows 10 receives new releases on an ongoing basis, which are available at no additional cost to users. Devices in enterprise environments can receive these updates at a slower pace, or use long-term support milestones that only receive critical updates, such as security patches, over their ten-year lifespan of extended support.

One of Windows 10’s most notable features is support for universal apps, an expansion of the Metro-style apps first introduced in Windows 8. Universal apps can be designed to run across multiple Microsoft product families with nearly identical code‍—‌including PCs, tablets, smartphones, embedded systems, Xbox One, Surface Hub and Mixed Reality.

Windows 10 also gets activated like all other older versions of the windows. You need to have a 25 digits Windows 10 Product key.

The Windows user interface was revised to handle transitions between a mouse-oriented interface and a touchscreen-optimized interface based on available input devices‍—‌particularly on 2-in-1 PCs, both interfaces include an updated Start menu which incorporates elements of Windows 7’s traditional Start menu with the tiles of Windows 8. Windows 10 also introduced the Microsoft Edge web browser, a virtual desktop system, a window and desktop management feature called Task View, support for fingerprint and face recognition login, new security features for enterprise environments, and DirectX 12.

Windows 10 received mostly positive reviews upon its original release in July 2015. Critics praised Microsoft’s decision to provide a desktop-oriented interface in line with previous versions of Windows, contrasting the tablet-oriented approach of 8, although Windows 10’s touch-oriented user interface mode was criticized for containing regressions upon the touch-oriented interface of Windows 8. Critics also praised the improvements to Windows 10’s bundled software over Windows 8.1, Xbox Live integration, as well as the functionality and capabilities of the Cortana personal assistant and the replacement of Internet Explorer with Microsoft Edge.

 However, media outlets have been critical of changes to operating system behaviors, including mandatory update installation, privacy concerns over data collection performed by the OS for Microsoft and its partners and the adware-like tactics used to promote the operating system on its release.

Microsoft aimed to have Windows 10 installed on at least one billion devices in the two to three years following its release. Up to August 2016, Windows 10 usage was increasing, with it then plateauing, while eventually in 2018, it became more popular than Windows 7 (though that is still more used in most countries in Asia and Africa) and thus the single most used Windows version overall (at 46.07%, thus the other more used overall), though not on some continents as measured by web traffic. As of November 2017, the operating system is running on more than 600 million devices and has an estimated usage share of 32% on traditional PCs and 15% across all platforms (PC, mobile, tablet, and console).