Books provide in-depth information and perspective that is important for academic research. In the sciences, most communication occurs through journals due to rapidly changing information, while in the humanities books are still key due to needing historical context. Old books remain valuable primary sources, even in sciences, though science books may become outdated. College libraries provide access to physical and electronic books through catalogs, databases, and interlibrary loans. Books offer additional references that can lead to more resources for research.