Catalog data are a library’s most important map to knowledge. What does it mean that the Library of Congress just released 25 million records to the public?

The library sought to arrange its collections on that model into the 19th century. As the number of books and libraries grew, a more systematic approach was needed.

Unfortunately, because of inconsistencies in the Library of Congress classification model, locating graphic novels in an academic library collection can be challenging.

For many years, the Library of Congress categorized many of its books under a controversial subject heading: “Illegal aliens.” But then, on March 22, 2016, the library made a momentous ...