Can someone please help me understand the role of Google Cloud Endpoints for web clients in a webapp?

Question

After reading the documentation for Cloud Endpoints, I can appreciate their usefulness in providing access to the App Engine webapp from Android and iOS platforms, but why would anyone use them for Javascript clients on their website when the website can directly access the App Engine app instances?

Maybe I am missing something really obvious being a novice! Many thanks to anyone who can educate me on this!!

Answer 1

AppEngine instances grant authenticated direct access to only JavaScript clients loaded from the website of that same instance. Endpoints provide a way for JavaScript clients hosted elsewhere to authenticate and access the instance content.