A derivative form of "ha ha ha" (signifying laughter), usually used in one of two ironic contexts.  

	* As a response to an unfunny, tasteless, insulting, or offensive comment by someone else.  The comment is offered in jest or as a joke, not as a serious insult; this is known to both.  One would not respond with HarHarHar to a deliberate insult or slur.
	* Pre-emptively, by the speaker of such a comment--often to signify that the comment is offered in jest.  i.e. ''English is an easy language to learn--even Americans can learn it.  HarHarHar''

On Wiki, we can use HarHarHar as a WikiBadge to identify such a comment....