Xbox Game Pass is a subscription-based service that allows users to play games from a library of select titles as much as they want, similar to the way Netflix operates. But unlike Netflix's traditional streaming setup, you'll download these games to your system before playing them. Should you want to purchase a Game Pass title outright, subscribers will receive an "exclusive" discount.
Alongside the launch date, Microsoft has also shared all of the games you'll be able to play through Game Pass at launch. Microsoft has said more than 100 games will be available, spanning a variety of genres. These won't all rotate out every month; instead, a "handful" of games will be removed or added monthly.
Xbox Game Pass is a separate service from Xbox Live Gold and costs $10/£8 per month, with no long-term subscription option available. T-Mobile subscribers will apparently be entitled to a free month at some point in June.