What is recovery check box in backup GUI?

Hello. In Windows Server 2012r2 backup GUI, under custom -> add items, in the select items window, there is a box that says “recovery”. This machine is a gen2 virtual machine. I have used backup on other 2012r2 servers and I don’t remember seeing it before. I have searched microsoft.com quite a bit and couldn’t find a reference to it. Can anyone explain what it is please? It is not selected when I pick bare metal. Why? Why is it not there in other instances of server backup on other machines? Are there any documents on Microsoft.com that explain this?
Thank you.