According to Copyright.gov, "A work of authorship is in the 'public domain' if it is no longer under copyright protection or if it failed to meet the requirements for copyright protection." Works in the public domain may be used free of charge for any purpose. Amazingly, the New York Public Library has recently placed more than 180,000 of the items in their Digital Collections in the public domain. Readers may like to explore several tools and projects designed to inspire use of the public domain resources. These include Visualize the Public Domain, where readers may scout the public domain resources by century, genre, collection, or color; Discover the Collections, where experts post blog entries inviting users to use the collections in interesting ways; and a series of Public Domain Remixes, in which NYPL staff have used public domain materials to create groundbreaking games and projects. In addition, readers may use the excellent search function to explore the digital collections and discover for themselves what might be useful.