Discovery layer is a term for software used to search libraries. A library's discovery layer includes a search box that library users can type queries into, similar to a web search engine. In library science, this searching is called discovery. The results from discovery may include books and other print materials from the library's catalog, electronic resources such as e-journals or videos, and items stored in other libraries. The word "layer" indicates that the software is modular—it is front-end software, separable from an integrated library system (ILS).