What is a Discovery Layer?
In terms familiar to most users, a discovery layer is a Google-like search across all library resources. In library language, a discovery layer is a searchable meta-index of library resources, usually including article-level metadata, e-book metadata, metadata from library catalogs, open access resource metadata, etc., and it includes a means of retrieving resources in the result set through linking technology.
In 2013, OhioLINK negotiated a contract for EBSCO Discovery Service (EDS) on behalf of the OhioLINK membership. In 2013, 58 OhioLINK libraries implemented EDS on their campuses – an OhioLINK initiative that was so successful, we celebrated in December with a combination party/round-table discussion, complete with cake.
Other OhioLINK libraries have chosen to implement other discovery layer products, such as Serials Solutions’ Summon and OCLC’s WorldCat Local, for even more discovery layer coverage across the state. So what is a discovery layer, and why did OhioLINK member libraries want to implement one?
Why is a discovery layer needed for libraries?
Without a discovery layer, users have to search many separate silos of information one by one – the library catalog for books and journals, publisher sites and individual ejournals in particular subjects for articles, and other specialized databases. Even for experienced users who know which databases and resources are likely to be most relevant to their needs, this is time-consuming and involves duplicating the same search over and over in different places. For novice users, or those who want a broad, interdisciplinary search, the initial choice of resource can be daunting and frustrating, unless users already know to ask their librarians for help. In addition, every database or resource interface is different – there are many similarities, but users have to learn different procedures and strategies for each information silo. While specialized interfaces deliver a lot of power for the advanced user, sometimes they can get in the way for other kinds of tasks.
Discovery layers offer a simple search box and consistent interface that allows searching across multiple resources, making it much easier to retrieve a variety of materials. The user can choose to limit the search by parameters particularly relevant to the academic environment, and refine the result set in powerful ways.
Why not just use Google or another search engine?
Many library resources are difficult to find using search engines, even if a user is savvy enough to be using Google Scholar or Microsoft Academic Search instead of regular Google or Bing. In addition, almost all online library resources, such as full-text articles and ebooks, are most decidedly not free or open access – academic libraries pay quite a bit of money for them (OhioLINK and its members invest approximately $38 million per year just for resources managed and negotiated via OhioLINK) and their use is restricted to the students, faculty, and staff at a particular academic institution. Finding an article, ebook, or other resource using general or specialized search engines doesn’t mean that the searcher will have access to it once he or she finds it; and even if the resource is available via the home library, there is usually no transparent and seamless way for these search engines to detect the searcher’s institutional affiliation, especially for anyone working remotely off-campus. 
Discovering library resources in a new way
By contrast, library discovery layers search only library resources; and only those resources that are available to the users at a particular institution. Not only are users guaranteed that they can access what they find, the search is also restricted to resources that have been determined by librarians to be accurate, current, and relevant for the particular curricular and research needs at their institution. Library discovery layers do an excellent job of filtering out much of the extraneous, inaccurate, or unobtainable results that can appear by using a general search engine.
Will discovery layers replace the many different databases and resources that academic libraries offer? Unlikely. Discovery layers are just another tool in the digital toolbox that OhioLINK libraries offer to their students, faculty, and staff. For more information about the discovery layer that may be in use at your institution, contact your own OhioLINK library. To further investigate discovery layers and why libraries choose them, view the archived discussion on American Libraries Live, where I joined Courtney Greene, head of Discovery & Research Services at Indiana University, and Edward Smith, executive director of the Abilene Library Consortium, to discuss “Making the Discovery Decision.”
