You can make archives of CDs and DVDs with Disk Utility. Put your CD or DVD in the drive and when it appears on the desktop, start Disk Utility, which is in your Utilities Folder and inside the Applications folder. (If iTunes or DVD Player start, quit them.)
When you see your CD/DVD in the left hand pane of Disk Utility, click once on it to highlight it (not the CD/DVD drive, but the disk icon just below it) and then go up to the File menu and pull down to New >.
In that menu, you will see “Disk Image from…” and the name of your CD/DVD. Select that, and then type in a name for the new disk image, and then select “Image format” which will be “DVD/CD Master,” and no encryption.
Then Disk Utility will begin the process, which could take a while, depending on the speed of your drive. A progress bar will appear to give you a idea of how long it will take.
Once the image is made, it will appear on the desktop. That’s your archive. Keep it on your hard drive or put it on another disk drive for safe keeping.
You can test it by double clicking on it; it will mount just like a real disk in your drive. (But eject that “disk” before you move the disk image.)
After you make an archive, you might have to delete the image from the sidebar of Disk Utility by highlighting it (click once on it) and then hitting Delete.
Now, if you want to make a CD/DVD copy of your archive, doubleclick on it and mount it. Then highlight it in the sidebar of Disk Utility. Put a blank CD/DVD in your drive, and when it spins up, click “Burn” in the menu bar of Disk Utility. You’ll need to click “Burn” in another box, and then you’ll see a progress bar. When the disk is burned, OS X will let you know.