Lightroom combines photos into "collections" - a virtual gathering of files, which can quickly do a search. It stores information about keywords, preview and metadata for each image file, and in a centralized database (engine SQLite). Therefore, the database can be accessed at the photos, which are now in the archives on DVD. Program size is much smaller than the Bridge, it runs faster and uses less memory. In general, Lightroom is targeted exclusively at photographers who are interested in processing and cataloging of photographs, rather than integration of everything. Another feature of the package Photoshop Lightroom - the separation process of working with images on separate stages. For each of them is a functional module with a corresponding set of tools and palettes settings.