A DVD Burner

Most Macs come with an internal SuperDrive — Apple's name for a CD and DVD reader/writer. If your Mac doesn't have a SuperDrive, and you want to back up or archive a lot of data, consider adding an external CD/DVD burner.

Another reason you might want an external DVD burner is that many Macs now come with a slot‐loading drive, which means you can't use mini‐DVDs that many cameras and camcorders now employ. Most external DVD burners are tray‐loading, making them more useful to mini‐DVD camera and camcorder users. And having two DVD burners makes duplicating your iDVD offerings and the like faster and easier.