The special tool we use here at The New Yorker for punching out the two dots that we then center carefully over the second vowel in such words as “naïve” and “Laocoön” will be getting a workout this year, as the Democrats coöperate to reëlect the President.
Those two dots, often mistaken for an umlaut, are actually a diaeresis (pronounced “die heiresses”; it’s from the Greek for “divide”). The difference is that an umlaut is a German thing that alters the pronunciation of a vowel (Brünnhilde), and often changes the meaning of a word: schon (adv.), already; schön (adj.), beautiful. In the case of a diphthong, the umlaut goes over the first vowel. And it is crucial. A diaeresis goes over the second vowel and indicates that it forms a separate syllable. Most of the English-speaking world finds the diaeresis inessential. Even Fowler, of Fowler’s “Modern English Usage,” says that the diaeresis “is in English an obsolescent symbol.”
The fact is that, absent the two dots, most people would not trip over the “coop” in “cooperate” or the “reel” in “reelect” (though they might pronounce the “zoo” in “zoological,” a potential application of the diaeresis that we get no credit for resisting). And yet we use the diaeresis for the same reason that we use the hyphen: to keep the cow out of co-workers.
Basically, we have three options for these kinds of words: “cooperate,” “co-operate,” and “coöperate.” Back when the magazine was just getting started, someone decided that the first misread and the second was ridiculous, and adopted the diaeresis as the most elegant solution with the broadest application. The diaeresis is the single thing that readers of the letter-writing variety complain about most.
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