Lee Feigenbaum is someone who jumps at the opportunity to spend 30 minutes reading a collection of questions and answers about hyphens, en dashes, and em dashes.
(The opportunity arose while composing another entry and struggling to figure out when I should type "-" vs. "–" vs. "—".)
Aren't you glad you now know that about me?
So what's the 30 second version? I'm someone who is only vaguely curious about such things...
grep for "World War" on that page for a great explanation...