docs: add section on actions vs remote schemas (close #4093)

CHANGELOG.md

@@ -39,6 +39,7 @@ Read more about the session argument for computed fields in the [docs](https://h
 - console: avoid count queries for large tables (#4692)
 - console: add read replica support section to pro popup (#4118)
 - cli: list all avialable commands in root command help (fix #4623)
+- docs: add section on actions vs. remote schemas to actions documentation (#4284)
 
 ## `v1.2.0`
 

docs/graphql/manual/actions/index.rst

@@ -133,6 +133,22 @@ How it works?
 * The action response is returned to the client synchronously or asynchronously
   based on the kind.
 
+Actions vs. remote schemas
+--------------------------
+
+Both actions and remote schemas can be used to extend Hasura with business logic.
+However, they have slightly different use cases.
+
+**Actions**
+
+Actions can be used when we want to call a REST endpoint from Hasura as a resolver for some custom types.
+They are especially useful for setting up serverless functions as resolvers.
+
+**Remote schemas**
+
+If you have an existing GraphQL API or if you're comfortable building a GraphQL server yourself,
+you can use :ref:`remote schemas <remote_schemas>` to add custom types and resolvers.
+
 Learn more
 ----------