Info-Mac

I can not open CDR files on my MACBOOK. Can someone suggest ways??

If this is a CDR audio archive, try dragging the file over the iTunes icon in your Dock and dropping it. If it's a CorelDRAW file you'll need CorelDRAW. A free demo is available at their site.

PS. A Mac is short for "Macintosh." It's not an acronym, thus it should not be capitalised.

To put it another way:
mac: a waterproof raincoat made of rubberized fabric
MAC: a data communication protocol sub-layer, also known as the Media Access Control
Mac: a brand name which covers several lines of personal computers designed, developed, and marketed by Apple Inc.

Ditto for iPod.