CorelDRAW Files Extensions - What are coreldraw files and how do I open a coreldraw file?

What are coreldraw files and how do I open a coreldraw file?

File Type Category File Format
.cdx CorelDRAW Files Compound Index File
.cmf CorelDRAW Files Cal3D Binary Mesh File
.cpd CorelDRAW Files RoboHelp Cache Project Database
.m3d CorelDRAW Files 3D Model File