Learn English – What’s the meaning and origin of “Herp Derp”

I've always been told and believed that \ˈī-thər\ (IPA /ˈaɪðər/) is the correct pronunciation, albeit both are indeed common nowadays. From what I am aware, etymologists and linguists believe this was the original pronunciation of the word too. Other contemporary Germanic languages (including the closest modern relatives, Dutch and German), suggest this pronunciation of the first syllable is correct — they have arguably been less altered/bastardised from Old Germanic. Old English (Anglo-Saxon) we know to be an almost purely Germanic language, and thus by simple statistical analysis (as is often employed in historical linguistics) we can be quite confident that this was the historically correct pronunciation.

Defining the word "sarcasm" is fairly straightforward. It usually means the expression of a sentiment whose opposite is meant. For example:

Hooray! I have a headcold.

Irony, however, eludes a simple explanation, and there tend to be disagreements about its meaning between UK and US speakers. Irony is found in the contrast between expected, or ordinary, outcomes and what actually happens. The greater the distance, the greater the irony.

For example: In this video, the police officer is giving a lecture on firearms safety, and shoots himself in the leg: http://www.youtube.com/watch?v=am-Qdx6vky0

That's an example of situational irony. And note that irony need not be funny, although it often is.