I use this as a reminder.

Mac OS X - Make a Backup of Your DVD or CD

I use OSX’s built in Disk Utility app for creating a backup image of my software discs. This way I can store them on a hard drive instead of worrying about losing the original disc. 

1. Insert disc.
2. Open Disk Utility under the Utilities folder.
3. Select the disc drive that the DVD resides in.

4. Select New Image from the toolbar.
5. Under ‘Image Format’ choose ‘DVD/CD master’.

6. Save wherever you’d like.