If you haven’t looked at the calendar yet today, it is a special day that won’t be repeated for a century: 12/12/12. The word twelve was early in the English language, forming in Old English as twelf literally meaning two left (over ten) as far back as the twelfth century! This system of counting came from the Proto Germanic formation *twa-lif-, a compound word formed by combining the root for two (*twa) and *lif-, which was the verb to leave. English has a stronger echo of to leave in the number eleven. Many Northern European languages adopted this formation: Old Saxon had twelif, Old Norse tolf, Old Frisian twelef, Middle Dutch twalef, and so on.
Commas are some of the most often misused punctuation marks, and with good reason. The rules that guide when and when not to insert a comma can be a bit clouded in terminology and exceptions. So often, though, it comes down to one question: Is it essential?
Want to know how an ice hotel works? Ever wondered about quantum suicide? Our team of know-it-alls isn’t afraid of a challenge. From car engines to search engines, from cell phones to stem cells, and thousands of subjects in between, HowStuffWorks has it covered. No topic is too big or too small for our editorial staff to unmask ... or for you to understand.