The present invention provides systems and methods for determining the originality of data content. In one embodiment, the determined originality of a particular item (e.g., a book) as compared to one or more other items can be used as a factor in recommending the item to a user. For example, in one embodiment, upon a user's selection of an item (e.g., a book), one or more items that have content most diverse from the selected item are determined and provided to the user. In another embodiment, various versions of an item are compared to each other to determine how content in each version differs from that in another version. In another embodiment, content in a collection of items are compared against content from publicly (freely) available sources (e.g., web pages) to determine the originality of the content in the collection of items.