Q: On the copyright page in almost every book, there is a long series of numbers and I don't know what they mean. Any ideas?

A: That string of numbers is such an oddity, it doesn't even have an official name, says Terry Emmrich, production manager for the University of Wisconsin Press.

Often called the "printings line" or simply the "numbers line," Emmrich says it designates whether the book you are holding comes from the first printing of that title, the second printing, the third printing and so forth. Book collectors appreciate this for helping identify authentic first printings. Everyday readers can use it to see if they have the most current version of a book.

By tradition starting in the 1940s, most publishers print a series of numbers on the copyright page and drop the lowest with each reprinting.

That means the lowest number typically represents the current printing, Emmrich says. So for the first printing, you will see "1 through 5," or "5 through 1," or a similar mix. In the second printing, the "1" will be deleted from the list, leaving "2" as the lowest number, and so on.

"The system isn't required, nor is the format standardized," Emmrich says. "The numbers' arrangement often simply depends on the design of the book."

- Produced in cooperation with University Communications

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