There was a time when metadata—descriptive information such as a book's title, author, or BISAC codes—was something only the warehouse crew had to worry about. "No one saw it," said Laura Dawson, CEO of, a consultant specializing in digital publishing services. "It was just warehouse data." But that was before the rise of online retailing at sites like and as well as the growth in the popularity and sales of e-books.

Now, Dawson said, accurate metadata has become a marketing tool for publishers, a shopping guide for consumers, and an absolute necessity for distributors and retailers. The growth of the importance of metadata, Dawson said, led to the creation of ONIX, or Online Information Exchange, an XML-based standardized format for transmitting information electronically. (XML, or extensible markup language, is a digital format that allows data to be easily reused in other forms.) XML software is said to be easy to use, inexpensive, and its tags or descriptions are easy for people, as well as machines, to read.

ONIX is used to transmit book metadata to anyone involved in selling, distributing, or organizing books. Originally devised by a coalition of publishers and retailers under the auspices of the Association of American Publishers, ONIX offers an extensive list of data fields (as many as 200) that can be used to describe a book—i.e., the metadata. Metadata includes not only title, author, and ISBN but availability, pricing, publisher name, reviews, blurbs, territorial rights, and jacket images and can include much more. ONIX is now jointly managed by the Book Industry Study Group in the U.S. in conjunction with partners in the U.K., Europe, and around the world.

But while using ONIX "is not complicated," Dawson said, the need for accurate data as well as the increasing number of book products—from multiple format e-books to audio books, large-print books, and vast increases in self-published titles—has led to something of a metadata overload. In fact, the importance of metadata could help save the beleaguered copyeditor's job, since metadata is only useful if it is accurate. Dawson called the situation "bloat" and pointed to the increasing cost and time needed to manage information that has become essential for selling books in today's marketplace.

Generally only the largest publishers can afford the staffing needed to manage their own metadata, while smaller publishers use companies like NetRead and Firebrand Technologies to manage and transmit their metadata. In the age of digital publishing, the more data available, the easier it is to sell or market a book. It's all about the metadata, said Greg Aden of NetRead, which produces Jacketcaster, a software product that helps publishers organize and transmit metadata to retailers, distributors, and libraries. "Accurate, rich metadata sells books," Aden said.

Andrew Savikas, v-p, digital initiatives, at O'Reilly Media, which also manages the metadata of about a dozen distribution clients, emphasized that the challenge facing publishers is to make sure the data is accurate throughout a proliferating number of book formats as well as an increasing number of retail and distribution channels. He considers diligence and "internal discipline" more important than the sophistication of the vendor or software used to manage metadata. "It's not the quality of the system but the consistency in using it," he said.

What happens, he said, if a title must be changed at the last minute? Is someone charged with correcting that metadata throughout all the channels?

While O'Reilly automates its metadata processes as much as possible, Savikas said the company makes sure there's an individual staffer who is responsible for checking data as it appears on, cover copy, catalogue copy, and elsewhere.

"There used to be consistency throughout the retail channel," Savikas said. "Amazon and B&N and other retailers all needed the same stuff." But that was before the appearance of channels like the Apple app store: "They need completely different data," Savikas said, pointing out the impact of agency model e-book pricing. "Now there may be four or five different prices for a single book."

"It's a constant struggle to get it right," Savikas said, "but it's critical to have reliable metadata."