The Xbox Series X and the Xbox Series S (collectively, the Xbox Series X/S) are home video game consoles developed by Microsoft. They were both released on November 10, 2020 as the fourth generation of the Xbox console family, succeeding the Xbox One family. Along with Sony's PlayStation 5, also released in November 2020, the Xbox Series X and Series S are part of the ninth generation of video game consoles.Rumors regarding the consoles first emerged in early 2019, with the line as a whole codenamed "Scarlett", and consisting of high-end and lower-end models codenamed "Anaconda" and "Lockhart" respectively. Internally, Microsoft had been satisfied with the two-console approach for the Xbox One, and planned a similar approach for the fourth generation Xbox, with the target for the high-end model to at least double the performance of the Xbox One X. The high-end model was first teased during E3 2019 under the title "Project Scarlett", while its name and design as Xbox Series X was unveiled during The Game Awards later in December. In September 2020, Microsoft unveiled the lower-end model as the Xbox Series S.
The Xbox Series X has higher end hardware, and supports higher display resolutions (up to 8K resolution) along with higher frame rates and real-time ray tracing; it also has a high-speed solid-state drive to reduce loading times. The less expensive Xbox Series S uses the same CPU, but has a less powerful GPU, has less memory and internal storage, and lacks an optical drive. Both consoles are designed to support nearly all Xbox One games, controllers, and accessories, including those games from older Xbox consoles supported by Xbox One's backwards compatibility. At launch, Microsoft positioned their first-party games and several third-party games to be available for both Xbox Series X/S and Xbox One to help transition between generations, providing the "Smart Delivery" distribution framework to freely provide further optimizations of an Xbox One game for either the Xbox Series X or Series S. The consoles are also compatible with the gaming subscription service Xbox Game Pass, as well as the cloud game-streaming platform Xbox Cloud Gaming.