The idea here is to embed links to other related resources in the requested resource, so that customers can follow these links to find available resources - just like people do with web browsers. For this, you often find the term HATEOAS (Hypertext As Enging of Application State).
If links are present (or not), the server can also inform the client that the following operations are possible or not.
To set links, you can put them in the http header or inside the body; for a later case, atom-pub format is used.
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