Color books are used to contain a collection of named, true (RGB) colors. Naming and categorizing the colors allows you to select colors by name rather than by number triplets. When a color from a book is assigned to an element, the book and color name are stored in the element and can be easily reviewed.

Color books can be stored in the open DGN file or more appropriately, as a shared resource in a DGN library. The following DGN libraries contain system color books:

• standardcolors.dgnlib — contains the Standard color book, a set of standard colors
• ral.dgnlib — contains the RAL CLASSIC, RAL DESIGN, and RAL EFFECT color books
• NCS.dgnlib — contains the Natural Color System® (NCS) color books

You can create additional color books that are standardized for your company, discipline, project or task.

The configuration variable MS_COLORBOOK_LIBRARIES points to the location of DGN libraries that contain the system color books — ..\Default\Colorbooks\ by default.