They are very similar to the internet troll.
1. A person who uses proper grammar at all times, esp. online in emails, chatrooms, instant messages and webboard posts; a proponent of grammatical correctness. Often one who spells correctly as well.
2. a – A person who believes proper grammar (and spelling) should be used by everyone whenever possible. b – One who attempts to persuade or force others to use proper grammar and spelling. c – One who uses proper grammar and spelling to subtly mock or deride those who do not; an exhibitor of grammatical superiority. d – One who advocates linguistic clarity; an opponent of 1337-speak. e – One who corrects others' grammar; the spelling police.
3. A nickname, pseudonym or handle for a well-known grammar nazi (defs. 1 and 2) within a particular social circle, used to show either great respect or great contempt for his or her abilities.
4. To correct the grammar of (a person's speech, a piece of writing, etc.); to edit for grammar and spelling; to proofread.
2. Teh grammar nazis haev invadd r formu.
3. Grammar Nazi, help me with my English homework please.
4. He totally grammar nazied my article, replacing pronouns and rewriting clauses.
In reality, they are making someone else feel bad for no reason and unintentionally implying that their "superior" grammar skills are all they have to show for a wasted liberal arts education.
While proper grammar usage is all well and good, a Grammar Nazi cavils even insignificant errors in English to somehow win an argument. Of course, rather than being genuinely persuasive in an argument, pointing out English errors is a weak attack only on the typist's credibility and never has any bearing on the underlying premises and assertions therein.
In other words, this is simply a disguised ad hominem argument which intelligent and logical people disregard.
Still, one should strive to spell and use words properly, but arrogant and unsolicited advice is not a very persuasive way to teach English.
Insecure English PhD (aka Grammar Nazi): I am in England studying here at Oxford, sir, and I prefer you talk to me only in Ye Olde Englishe like a good chap because language can never evolve.
Some High Schooler: LOL!!!!11 Hve fun nvr getting laid!1111!!!!
When a literate is in Grammar Nazi mode, they are usually found correcting all sorts of typos & grammar and/or punctuation errors.