What happens when someone clicks 'unsubscribe' in a zoho CRM email

What happens when someone clicks 'unsubscribe' in a zoho CRM email

Hello,

As per, i am going round in circles trying to find an answer to these 2 question.

I have an email template that has an unsubscribe link in the footer in zoho CRM.

First, what happens when someone clicks it - where does the contact get unsubscribed from? is it a full email opt out?

Secondly - what happens when I create a new unsubscribe link add that to the email instead and a contact clicks it.

I know in developer > webforms > unsubscribe link - you can 'set the action' but this does not give clear indication of what is happening and nor can I find any documentation, anywhere.

Thanks in advance