When a disc is a disk and vice versa...

In an interesting knowledge base article, Apple clears up one of the age old computing confusions.  Namely, what is the difference between a disc and a disk?  While there is no ground-breaking revelations in the article, I found it to be noteworthy.  Often computer terms are mixed up or misused.
Using the proper language when diagnosing issues can be the difference between hours of work.  How many times have you heard someone say they couldn't connect to "the Google"?

What is a disc?
Discs are optical media such as an audio CD, CD-ROM, DVD-ROM (or RAM), or a DVD-video disc.  Discs also include recordable media, such as CD-R and DVD-R.  All discs are removable, meaning they eject from your Mac.

What is a disk?
Disks are magnetic media, like your built-in hard disk.  Disks also refer to external hard drives and are always rewritable, unless otherwise protected with software.  Disks can be partitioned into smaller sections and be given different functions.

So, the next time you are having an issue with a DVD that is not playing, you will be able to tell the Genius at the Apple Store that your d-i-s-c is not playing properly.  Or, if your internal hard drive is acting up, you can tell AppleCare that you seem to be having a d-i-s-k problem.

Um?