The term "book sales" refers to the total number of books that have been sold or purchased by consumers over a specific period of time. This can include both physical and digital copies of books, depending on the context in which it is being used. Book sales are an important metric for publishers, authors, and bookstores as they provide insight into the popularity and demand for particular titles. High book sales can indicate that a title is performing well and may warrant further investment from the publishing company, while low book sales could signal that a title needs to be reassessed or potentially discontinued. Overall, "book sales" refers to the commercial success of books in the marketplace.