# Create an Application

When integrating with our API or authentication system, you’ll first need to **register an application** (more accurately an OAuth Client). This registration process creates the credentials that identify your app — specifically, a **Client ID** (and sometimes a **Client Secret** dependencing on your application type) — that enable OAuth-based authentication and authorization.

## What is a Client ID?

A **Client ID** is a unique identifier issued to your application when it’s registered with the authorization server. It represents your app in the OAuth terminology — much like a username for your app.

* It’s publicly visible (e.g., in API requests, JavaScript code, or redirects).
* It helps the authorization server recognize which app is making a request.
* It’s paired with a **Client Secret** for confidential applications to authenticate securely.

Think of it as the way the system knows, “This request is coming from *your* app.”

## Select your Application Type

When registering your app, make sure to **select the application type** that best matches your environment and security model — see the [application-types](https://docs.bluenexus.ai/getting-started/create-an-application/application-types "mention") section for guidance on which option to choose.

## Scopes

Scopes define what your application can access on behalf of a user or service. When creating or editing your **Client ID**, you’ll need to choose the scopes your app requires.

1. **Identify your app’s needs** — what data or actions does it require?
2. **Select only the necessary scopes** — this limits access and improves security.
3. **Add the scopes to your OAuth request** — e.g. `scope=account user-data`.
4. **Review the consent screen** — users will see and approve the scopes you request.

{% hint style="info" %}
Read [understanding-scopes](https://docs.bluenexus.ai/getting-started/create-an-application/understanding-scopes "mention")for a detailed understanding of how they work or see the [Scopes Reference](https://docs.bluenexus.ai/platform/api/scopes) for a list of all available scopes.
{% endhint %}