The ArcCatalog application provides a catalog window that is used to organize and manage various types of geographic information for ArcGIS Desktop. The kinds of information that can be organized and managed in ArcCatalog includes:
Geodatabases
Raster files
Map documents, globe documents, 3D scene documents, and layer files
Geoprocessing toolboxes, models, and Python scripts
GIS services published using ArcGIS Server
Standards-based metadata for these GIS information items
And much more
ArcCatalog organizes these contents into a tree view that you can work with to organize your GIS datasets and ArcGIS documents, search and find information items, and to manage them.
ArcCatalog presents this information in a tree view and allows you to select a GIS item, view its properties, and to access tools to operate on the selected item(s).