The Library allows you to temporarily save your favourites when you're browsing. They disappear when you log out.
The Wishlist allows you to save your favourites without losing them when you logout.
To use the Wishlist you must first register an Account... you can then Login and access your choices safely kept in your Wishlist from any computer...worldwide, anytime.
Once Logged in, clicking "Move To List" (which is only shown when logged in...) will swap an item between the Library and your Wishlist...and vice versa