NoteTab clipbar file CTB file suffix is associated with NoteTab. File contains clipbar.
Custody Toolbox data file.
File used by AutoCAD, a CAD program used for 2D and 3D drawing; contains color-based plot styles, or mappings of colors to layers of objects; used to attach color and display settings to design objects. CTB files have been updated to .STB files, which abstract layer color-based properties to object-based properties. Many companies still use CTB files instead of STB files because of the cost required to train personnel and to upgrade existing CAD designs.