Cd Files on PC to MAC

I have a yamaha cdrw2100e cd/rw recorder and am using windows 95. I have created data disks with several jpeg files and sent them to several different people. Some of the mac users cannot open the files. They change from jpeg files to backup files.

Am I doing something wrong? How can I make the disk/files mac compatable? Please help me or tell me where I can get some help – soon!

Thanks
Kevin Bouck
twsales@idacom.net