Files with the .CDC extension contain images that function as miniatures of drawing projects, generated during catalog browsing with the large image icon preview option on. It is generated and used by DesignCenter tools of the AutoCad software. Data contained in CDC files are used for buffering file miniatures, which optimizes the browsing process. Thanks to them, the AutoCad software does not need to generate previews of drawings located in a browsed catalog each time said catalog is opened. CDC files can be safely removed without affecting the original drawing.