If you've ever turned over a book, you've seen the barcode on the back. That code represents the ISBN--the International Standard Book Number. Every book has its own unique number. Until now, they've been 10-digit numbers. The first set of digits represents the language--0 and 1 for English, 2 for French, 3 for German, and so on up to 99963 for Cambodian. The next set is the publisher's code, followed by the title identifier. The last digit is the check digit. (A fuller explanation of the system is here.)
Plenty of numbers, right? Actually, no. We're running out of ISBNs under this system. The solution is to move to the new, improved 13-digit ISBN. At first, this just meant tacking "978-" to the front of the old ISBN. That doesn't solve the problem, and today it was announced that phase two of the plan has begun. The first "979-" prefixes have been assigned to the French book numbering authority. It's a new era. It is now possible to have duplicate 10-digit ISBNs; the only distinction is in the prefix. I know this doesn't mean much to the average book buyer, but trust me, it's a big deal among people who are concerned with bibliographic databases.
So spend a moment today in silent thanks for the geeks who keep the book industry running smoothly. They're working hard. Details--for anyone who's still reading this article--are here.--David E