You will create a number of information products when you use ArcGIS—for example, geodatabases and datasets, map documents, geoprocessing models, raster files, metadata, services, and so on. ArcGIS Desktop 9.3 and 9.3.1, includes ArcCatalog—an application where you organize, document, and manage your ArcGIS information in workspace folders and geodatabases.
To learn more, see Workspace and dataset management with ArcCatalog