Which Windows version introduced the Cortana digital assistant?

Windows 10 was the first desktop Windows version to introduce the Cortana digital assistant. Cortana was built into Windows 10 as a voice- and text-driven helper that could answer questions, search the device and web, create reminders, and connect with Microsoft services.

The assistant was named after a character from Microsoft’s Halo video-game series, and the Halo connection helped make the feature distinctive during Windows 10’s launch campaign. Cortana was closely integrated with the taskbar search experience and could be activated through speech on supported devices.

A common mix-up is that Cortana appeared before Windows 10 on Windows Phone 8.1, which launched in 2014. That does not make Windows Phone the answer to this desktop Windows question. Windows 10 brought the assistant to Microsoft’s PC operating system, beginning with version 1507, released to the public on July 29, 2015. Later Windows releases reduced Cortana’s system-wide role and treated it more like a standalone application.