My Wife, My Daughter, Their Periods, and the Space They Need

Generational gaps exist on all levels, even grammatical. What was once right is now wrong and vice versa. Two nights ago, my wife and my daughter were going over some work together. That is where the fun begins, at least for me. With all good intentions, my wife set out to offer some constructive advice and to correct an item in my daughter's writing; my daughter had only put one space after the period at the end of each sentence and before the next sentence. One space in between sentences. Anyone above the age the age of forty can tell you that is just wrong. Wrong, wrong, wrong. Anyone who learned to type on a typewriter can tell you that there must be two spaces after the period and before the next sentence. Anyone who tells you this is wrong. Period!

As my daughter not so gently, politely, or respectfully pointed out, it is now proper to insert only one space between sentences. Without getting into too much discussion about mono-spacing and true type fonts, suffice it to say that "The times, they are a changing." My wife, of course, looked to me for support of her position. Unfortunately, since I had already been enlightened on this particular topic, I was of no help to her. In fact, I may have not so gently, politely, or respectfully pointed out that my daughter was correct.

What other grammatical generational gaps are out there, and where is the memo?