Building custom Ribbon UI in AutoCAD is important for AutoCAD only Macro's
With AutoCAD cui Client Can easliy use it's macro, without remembering any commands
Steps to create new CUI
We need two files for this
DVB File: This contain vba project
CUI File: This contain Ribbon UI Autocad
DVB File
You can create DVB file using AutoCAD VBA Editor
Put DVB file into AutoCAD Support Folder in Programfiles for easy access
CUI File
You can create CUI file Using AutoCAD CUI Editor
You can keep CUI File whereever you like, You have to load it only once usign CUILOAD command and it will get automatically loaded whever you'll open new autoCAD