I can remember when I was in high school, in my senior year of English, they began telling us that it was no longer proper to have the salutation of "Gentlemen:" in business letters. (Of course, I still address business letters that way and always will, just to spite those fuckers. Political correctness be damned). It had to be "Dear Madam or Sir". That was my first known encounter with it. Then, in college, it became unacceptable to use "he" as the generic pronoun. Textbooks would use sentences with "she" where "he" would have been expected, that made the sentence sound silly. Such as: "When operating a jackhammer the user should be sure she is wearing safety goggles" or "The fighter pilot safely ejected with only minor injuries to her knees." Then "he or she" or "s/he" became the correct pronoun usage.

What and when does everyone remember of their first encounter with PC?