My husband loves giant dictionaries so of course he looked the words up and we discussed them (he was closer to it than I). He studied with a teacher at Ohio State who had the nerve to give him a grade less than an A on an essay. When he asked why, the instructor told him the essay was poorly written, outlined some of the problems and so he went off and rewrote it and turned it in. When he still did not get an A, he asked why? The instructor replied, because you didn't do it right the first time. My husband never forgot the lesson. Because of this, I often rely on his editing to check my work for my worst habits.
I could rant about perfection when we are all supposed to be imperfect humans capable of mistakes or the inequities of grades upon one's future, but that would keep me off my topic.
So what is the difference between facetious, ironic, sardonic, wry and sarcastic?
I had someone tell me I was sarcastic recently and it turns out the terms was used wrong because sarcasm is intended to hurt, whereas I had made a positive statement about something and there was no intention to hurt at all. Because I referred to the item in an exaggerated fashion, I was in fact using irony.
A facetious statement is one said jokingly, with light humor, intending to be frivolous, or amusing.
An ironic statement is one of feigned ignorance, often meaning the opposite of the literal sense.
A sarcastic statement is a mean statement, meant to hurt someone and marked by bitterness, is caustic i.e. intended to sting.
A sardonic statement expresses derision, comtempt, a cynical attitude and is negative or cutting.
A wry statement is often mischievous, perverse or contrary to the right meaning, wrong-headed or twisted, sometimes with bitterness.
The distinction can be minimal and hard to follow in conversations, especially over the internet when there is no facial expression or tone to carry the proper sense in the way the words are stated.
Still, the value of humor is to disarm people and allow them to laugh at themselves. If humor is used against oneself, then damage is less likely. Humor breaks barriers between people and allows a level of honesty that seldom arises in formal settings.
On the internet, the use of lol, or laughing out loud, ha ha, or just kidding or teasing, also indicates there was no harm meant.