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

# Users

> 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](/build/core-features/common/user/player-identity-xuser)
Describes how XBOX One 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)](/build/core-features/common/user/gamecore-user-models)
Describes the two users models available in the GDK

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

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

[Changing the Default User for the Game (NDA topic)](/build/core-features/common/user/users-changing-default-user)
Describes how to change the default user for the game

[Dealing with Controller Loss (NDA topic)](/build/core-features/common/user/users-dealing-with-controller-loss)
Describes how games should deal with controller loss

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

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

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

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

[Users and input devices](/build/core-features/common/user/users-input-devices)
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 identity and XUser](/build/core-features/common/user/player-identity-xuser.md)
- [XUser](/reference/system/xuser/xuser_members.md)
- [XUserIsStoreUser](/reference/system/xuser/functions/xuserisstoreuser.md)
- [User identity](/services/xbox-services/fundamentals/identity/xs-identity-overview.md)
- [User profile](/services/xbox-services/fundamentals/identity/user-profile/index.md)