                   Find a book            Borrow it             Return it
               --------------------  --------------------  --------------------
First release  +------------------+  +------------------+  +------------------+
               | Search by title  |  |  Borrow at the   |  |  Return at the   |
               +------------------+  | desk with a card |  |       desk       |
               +------------------+  +------------------+  +------------------+
               | See if a copy is |
               |   on the shelf   |
               +------------------+
===============================================================================
Next           +------------------+  +------------------+  +------------------+
               | Search by author |  |  Reserve a copy  |  | Reminder before  |
               +------------------+  |   that is out    |  |   the due date   |
                                     +------------------+  +------------------+
...............................................................................
Later          +------------------+  +------------------+
               | Recommendations  |  |   Self-service   |
               +------------------+  |      kiosk       |
                                     +------------------+
