Fix OAuth terminology in topics

doc/api/oauth2.md

@@ -5,15 +5,15 @@ group: Access
 info: To determine the technical writer assigned to the Stage/Group associated   with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
 ---
 
-# GitLab as an OAuth 2.0 provider **(FREE)**
+# OAuth 2.0 identity provider API **(FREE)**
 
-This document covers using the [OAuth2](https://oauth.net/2/) protocol to allow
-other services to access GitLab resources on user's behalf.
+GitLab provides an API to allow third-party services to access GitLab resources on a user's behalf
+with the [OAuth2](https://oauth.net/2/) protocol.
 
-If you want GitLab to be an OAuth authentication service provider to sign into
-other services, see the [OAuth2 authentication service provider](../integration/oauth_provider.md)
-documentation. This functionality is based on the
-[doorkeeper Ruby gem](https://github.com/doorkeeper-gem/doorkeeper).
+To configure GitLab for this, see
+[Configure GitLab as an OAuth 2.0 authentication identity provider](../integration/oauth_provider.md).
+
+This functionality is based on the [doorkeeper Ruby gem](https://github.com/doorkeeper-gem/doorkeeper).
 
 ## Supported OAuth 2.0 flows
 
@@ -25,7 +25,7 @@ GitLab supports the following authorization flows:
 - **Authorization code:** Secure and common flow. Recommended option for secure
   server-side apps.
 - **Implicit grant:** Originally designed for user-agent only apps, such as
-  single page web apps running on GitLab Pages).
+  single page web apps running on GitLab Pages.
   The [Internet Engineering Task Force (IETF)](https://tools.ietf.org/html/draft-ietf-oauth-security-topics-09#section-2.1.2)
   recommends against Implicit grant flow.
 - **Resource owner password credentials:** To be used **only** for securely

doc/integration/oauth_provider.md

@@ -4,18 +4,16 @@ group: Access
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
 ---
 
-# GitLab as an OAuth 2.0 authentication service provider
+# Configure GitLab as an OAuth 2.0 authentication identity provider
 
-This document describes how you can use GitLab as an OAuth 2.0
-authentication service provider.
+This document describes how you can use GitLab as an OAuth 2.0 authentication identity provider.
 
-If you want to use:
-
-- The [OAuth 2.0](https://oauth.net/2/) protocol to access GitLab resources on
-  a user's behalf, see [OAuth 2.0 provider](../api/oauth2.md).
-- Other OAuth 2.0 authentication service providers to sign in to
-  GitLab, see the [OAuth 2.0 client documentation](omniauth.md).
-- The related API, see [Applications API](../api/applications.md).
+- OAuth 2 applications can be created and managed using the GitLab UI (described below)
+  or managed using the [Applications API](../api/applications.md).
+- After an application is created, external services can manage access tokens using the
+  [OAuth 2 API](../api/oauth2.md).
+- To allow users to sign in to GitLab using third-party OAuth 2 providers, see
+  [OmniAuth documentation](omniauth.md).
 
 ## Introduction to OAuth
 

doc/topics/authentication/index.md

@@ -43,7 +43,7 @@ This page gathers all the resources for the topic **Authentication** within GitL
 - [Personal access tokens](../../api/index.md#personalproject-access-tokens)
 - [Project access tokens](../../api/index.md#personalproject-access-tokens)
 - [Impersonation tokens](../../api/index.md#impersonation-tokens)
-- [GitLab as an OAuth2 provider](../../api/oauth2.md#gitlab-as-an-oauth-20-provider)
+- [OAuth 2.0 identity provider API](../../api/oauth2.md)
 
 ## Third-party resources
 

doc/user/project/clusters/runbooks/index.md

@@ -63,8 +63,9 @@ information.
 Follow this step-by-step guide to configure an executable runbook in GitLab using
 the components outlined above and the pre-loaded demo runbook.
 
-1. Create an [OAuth Application for JupyterHub](../../../../integration/oauth_provider.md#gitlab-as-an-oauth-20-authentication-service-provider).
-1. When [installing JupyterHub with Helm](https://zero-to-jupyterhub.readthedocs.io/en/latest/jupyterhub/installation.html), use the following values
+1. Create an [OAuth application for JupyterHub](../../../../integration/oauth_provider.md).
+1. When [installing JupyterHub with Helm](https://zero-to-jupyterhub.readthedocs.io/en/latest/jupyterhub/installation.html),
+   use the following values:
 
    ```yaml
    #-----------------------------------------------------------------------------