fixed minor grammar bug

Author: R-C-Stewart

learn-pr/wwl-azure/explore-identity-azure-active-directory/includes/4-discuss-identity-control-plane.md

@@ -1,5 +1,5 @@
 :::image type="content" source="../media/control-plane.png" alt-text="Diagram of identity and access management working as a controller for access to all resource.":::
 
-What is a control plane?  A **control plane** is a term that used for years within networks. It's the part of a network that routes network traffic around the network architecture. So, a control plane is a tool or service that directs access to resources based on specific criteria. When it comes to solutions in today's world, the user identity is the right place to check for access. Identity is a clear choice for the control plane.
+What is a control plane? A **control plane** is a long-established networking concept. It's the component responsible for determining how traffic flows through a network. So, a control plane is a tool or service that directs access to resources based on specific criteria. When it comes to solutions in today's world, the user identity is the right place to check for access. Identity is a clear choice for the control plane.
 
 With the many networks, devices, and applications needed in daily business, the only common denominator is the identity. Every user, external user, app, and device have an identity. So, we say identity is the control plane. It’s critical to establish who the user is as the core of trust for other transactions. If we aren’t sure who the user is, no other system access control or security matters. Once we're sure of the user, we can explicitly verify every element of access whether our resources are on-premises, in cloud-hosted servers, or managed SaaS apps like Office 365.