.INCD File Extension

File used by Adobe InCopy, a professional writing program that integrates with Adobe InDesign; contains document text, graphics, page formatting, and styles; often used for editing smaller portions of a larger document.

INCD files are the older version of .ICML files. They can still be opened with InCopy and InDesign, but you should save InCopy documents using the .ICML extension in newer versions of the software.