Lets look at the last two in detail. You must receive approval from the list owner to subscribe to a closed list.
Lists can be Public or Private Anyone can find out who is subscribed to a public list.
Only current subscribers can find out who is subscribed to a private list. Every submission to a moderated list must be approved by the list owner. No approval is necessary to send a submission to the list. List can be Archived or not. A permanent archive of submissions is kept in an archived list.