The Completed shelf in your account stores every item that you rate or comment on. You can also add titles directly to this shelf from search results, title records, your other shelves, checked out or holds lists, or your borrowing history. You can add as many items as you'd like. The shelf can be sorted by date added, title, author or rating and filtered by format, audience, etc.
The Completed shelf is a good alternative to borrowing history if you would like more options for displaying or organizing your items. Borrowing history is a separate tool you can to opt into that keeps track of all your borrowed physical materials over time.
All shelves are public by default but can be made private, either the entire contents of the shelf (log in and go to My Settings) or individual items on the shelf (use the "Add Details" dropdown menu for the item on your shelf).
Use the Help link in the catalog for detailed information.