From the outset of “This Book Is Overdue,’’ Marilyn Johnson introduces today’s librarians as cybrarians, a “new breed of tech-savvy librarians, part cyborg, part cat’s eye reading glasses.’’ As Johnson amply shows in her romp through the brave new world of the profession, these new librarians cum information scientists are building on the work of their pioneering predecessors as they branch out in sometimes surprising directions.

A librarian, the late Henriette Avram, gave Johnson her motivation for writing “Overdue.’’ Johnson, who is also the author of “The Dead Beat: Lost Souls, Lucky Stiffs, and the Perverse Pleasures of Obituaries,’’ came across Avram’s obituary and learned about the storied transformation of millions of dog-eared catalog cards in the Library of Congress into a searchable electronic database in the late 1960s and early 1970s. Avram’s MARC project – Machine Readable Cataloging – quickly guided librarianship into the shiny new field of information science.