> ## Documentation Index
> Fetch the complete documentation index at: https://docs.xbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Users (contents)

> Users

This section describes the Microsoft Game Development Kit (GDK) concept of a user, how a user is represented as an `XUser`, and the relationship of a user to input devices.

## In this section

[User identity and XUser](https://docs.xbox.com/build/core-features/common/user/player-identity-xuser.md)
Describes how XBOX Series X|S manages the identity of the users interacting with the game with an `XUser` object. Each `XUser` instance represents a user who is signed in to the game.

[GDK User Models (NDA topic)](https://docs.xbox.com/build/core-features/common/user/gamecore-user-models.md)
Describes the two users models available in the GDK

[Opting into Default User Required (NDA topic)](https://docs.xbox.com/build/core-features/common/user/users-opting-into-simplified-model.md)
Describes how to opt into ensuring the game has a default user at launch

[Establishing the Default User for the Game (NDA topic)](https://docs.xbox.com/build/core-features/common/user/users-establishing-default-user.md)
Describes how to establish the default user in the game.

[Changing the Default User for the Game (NDA topic)](https://docs.xbox.com/build/core-features/common/user/users-changing-default-user.md)
Describes how to change the default user for the game

[Dealing with Controller Loss (NDA topic)](https://docs.xbox.com/build/core-features/common/user/users-dealing-with-controller-loss.md)
Describes how games should deal with controller loss

[When do user-to-controller associations take place? (NDA topic)](https://docs.xbox.com/build/core-features/common/user/users-timing-of-user-to-device-association.md)
Describes when user-to-controller associations take place.

[Guest users overview](https://docs.xbox.com/build/core-features/common/user/users-guest-overview.md)
Describes XBOX Guest Accounts and their interaction with XBOX services.

[Headless automation of XUser](https://docs.xbox.com/build/core-features/common/user/users-headless-automation.md)
Describes how games can use automation with `XUser`.

[How to: best practice to sign in a user](https://docs.xbox.com/build/core-features/common/user/xuser_howto_best_practice_signing_in.md)
Demonstrates the best practice to sign in and establish an initial user.

[Users and input devices](https://docs.xbox.com/build/core-features/common/user/users-input-devices.md)
Describes how games determine which input devices are associated to a specified user.

## See also

[System](https://learn.microsoft.com/build/archive/gc-system-toc)


## Related topics

- [User profile (contents)](https://docs.xbox.com/services/xbox-services/fundamentals/identity/user-profile/live-user-profile-toc.md)
- [user_statistics_c (contents)](https://docs.xbox.com/reference/live/xsapi-c/user_statistics_c/user_statistics_c_members.md)
- [XUser (API contents)](https://docs.xbox.com/reference/system/xuser/xuser_members.md)
- [User sign-in (contents)](https://docs.xbox.com/services/xbox-services/fundamentals/identity/auth/live-authentication-nav.md)
- [User achievements systems (contents)](https://docs.xbox.com/services/xbox-services/player-data/achievements/live-achievements-nav.md)