Clarify different between API Gateway and Gateway API

Author: david-martin

site-src/faq.md

@@ -54,13 +54,33 @@
 * **Q: Which Kubernetes versions are supported?<br>**
   A: See our policy on [Supported Version](https://gateway-api.sigs.k8s.io/concepts/versioning/#supported-versions)
 
-* **Q: Is SSL Passthrough supported?**
+* **Q: Is SSL Passthrough supported?<br>**
   A: SSL Passthrough (wherein a Gateway routes traffic with the [Transport
   Layer Security (TLS)][tls] encryption _intact_ to a backend service instead of
   terminating it) is supported by [TLSRoutes][tlsroute]. See the
   [TLS Guide][tlsguide] for more details about passthrough and other TLS
   configurations.
 
+* **Q: What's the difference between Gateway API and an API Gateway?<br>**
+  A: An API Gateway is a general concept that describes anything that exposes
+  capabilities of a backend service, while providing extra capabilities for
+  traffic routing and manipulation, such as load balancing, request and response
+  transformation, and sometimes more advanced features like authentication and
+  authorization, rate limiting, and circuit breaking.
+  Gateway API is an interface, or set of resources, that model service networking
+  in Kubernetes. One of the main resources is a `Gateway`, which declares the
+  Gateway type (or class) to instantiate and its configuration. As a Gateway
+  Provider, you can implement the Gateway API to model Kubernetes service
+  networking in an expressive, extensible, and role-oriented way.
+  Most Gateway API implementations are API Gateways to some extent, but not all
+  API Gateways are Gateway API implementations.
+
+* **Q: Is Gateway API a standard for API Management?<br>**
+  A: No. API Management is a much broader concept than what Gateway API aims to
+  be, or what an API Gateway is intended to provide. An API Gateway can be an
+  essential part of an API Management solution. Gateway API can be seen as a
+  way to standardize on that aspect of API Management.
+
 [1]: https://github.com/kubernetes-sigs/gateway-api
 [2]: https://github.com/kubernetes-sigs/gateway-api/releases
 [tls]:https://en.wikipedia.org/wiki/Transport_Layer_Security

site-src/index.md

@@ -1,7 +1,7 @@
 ## What is the Gateway API?
 
 Gateway API is an open source project managed by the [SIG-NETWORK][sig-network]
-community. It is a collection of resources that model service networking 
+community. It is an API (collection of resources) that model service networking
 in Kubernetes. These resources - `GatewayClass`, `Gateway`, `HTTPRoute`, 
 `TCPRoute`, `Service`, etc - aim to evolve Kubernetes service networking through 
 expressive, extensible, and role-oriented interfaces that are implemented by 
@@ -94,8 +94,24 @@ This flexibility allows the API to adapt to vastly different
 organizational models and implementations while remaining a portable and
 standard API.
 
+## What's the difference between Gateway API and an API Gateway?
 
-## Who is working on Gateway?
+An API Gateway is a general concept that describes anything that exposes
+capabilities of a backend service, while providing extra capabilities for
+traffic routing and manipulation, such as load balancing, request and response
+transformation, and sometimes more advanced features like authentication and
+authorization, rate limiting, and circuit breaking.
+
+Gateway API is an interface, or set of resources, that model service networking
+in Kubernetes. One of the main resources is a `Gateway`, which declares the
+Gateway type (or class) to instantiate and its configuration. As a Gateway
+Provider, you can implement the Gateway API to model Kubernetes service
+networking in an expressive, extensible, and role-oriented way.
+
+Most Gateway API implementations are API Gateways to some extent, but not all
+API Gateways are Gateway API implementations.
+
+## Who is working on Gateway API?
 
 The Gateway API is a
 [SIG-Network](https://github.com/kubernetes/community/tree/master/sig-network)