Client credentials to get TOKEN of Facebook

This page doesn't explains which client credentials we have to use.

https://developers.facebook.com/docs/authentication/applications/

https://graph.facebook.com/oauth/access_token?
    client_id=YOUR_APP_ID
   &client_secret=YOUR_APP_SECRET
   &grant_type=client_credentials

Any clue what is that?

Does it make sense https://developers.facebook.com/docs/authentication/permissions/ also?

Thank you!

What is a token credential?

In computer systems, an access token contains the security credentials for a login session and identifies the user, the user's groups, the user's privileges, and, in some cases, a particular application.

How do I get a long term access token on Facebook?

At a high level, you obtain a long-lived token for the client by: Using a valid, long-lived access token, your server sends a request to get a code from Facebook. Facebook sends a code back to your server and you securely send this code to the client.