It is not easy to detail all the technological and conceptual developments that are emerging in the world of OPACs and being defined as new-generation catalogs. Try to give a brief outline of what is happening in a market which, thanks to the efforts of Open Source and the emergence of new technologies and services, is awakening from decades of lethargy, which should provide an opportunity for the sector, and therefore, to the user.
Customization and User Participation: The concept of “My Library” has become ubiquitous in library OPACs and portals. In the vast majority of OPACs, the user can reserve items or renew loans online, create lists of favorites, receive alerts and personalized recommendations based on search history or popular items among similar users, and so on.
The social OPACs are those that allow the user's active participation both within the “life” of the library (which would lead to the concept of Library 2.0), and in enriching the search experience of finding and discovering items in the catalog. Thus, users are now able to assess, recommend, criticize and even collaborate in the item´s bibliographic description, with tags social indexing, and construction of the Catalogue, which was already the user through the classical desiderata, but now a form perhaps more deliberate and visible (Coyle, 2007) (see Figure 1).