docs(angular): add http-client content (#6443)

src/data/roadmaps/angular/content/http-client@8UY0HAvjY7bdbFpt-MM1u.md

@@ -1 +1,9 @@
-# HTTP Client
+# HTTP Client
+
+Most front-end applications need to communicate with a server over the HTTP protocol, to download or upload data and access other back-end services. Angular provides a client HTTP API for Angular applications, the `HttpClient` service class in `@angular/common/http`.
+
+Visit the following resources to learn more:
+
+- [@official@Angular Official Docs - HTTP Client](https://angular.dev/guide/http)
+- [@article@Angular HTTP Client - Quickstart Guide](https://blog.angular-university.io/angular-http/)
+- [@article@Using HTTP Client in modern Angular applications](https://www.thisdot.co/blog/using-httpclient-in-modern-angular-applications)