# Users

The **User SDK** makes it seamless for you to integrate Sudo capabilities into your applications with minimal effort. For applications that support Open ID Connect, the **User SDK** enables applications to map their existing users to Sudo Platform users without the need for end users to create new accounts.

## Key Features

|                            |                                                                                                                                                                                                          |
| -------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Private Key Authentication | The **User SDK** allows your users to on-board with minimal effort and sharing of personal information. Private Key Authentication offers a modern, passwordless approach for signing up and logging in. |
| Federated Authentication   | The **User SDK** offers multiple ways to register a user, including Federated Sign In (via OIDC).                                                                                                        |

## Next Steps

* Integrate the **User SDK** into your [JavaScript](https://docs.sudoplatform.com/guides/integrate-the-user-sdk#integrate-the-js-sdk), [iOS](https://docs.sudoplatform.com/guides/integrate-the-user-sdk#integrate-the-ios-sdk) and [Android](https://docs.sudoplatform.com/guides/integrate-the-user-sdk#integrate-the-android-sdk) applications
* Learn more about [Sudo digital identities](https://docs.sudoplatform.com/concepts/sudo-digital-identities) and other core concepts