As it turns out, I have been cheating at table tennis my entire life
I really didn't know this was the case until recently when I was in the presence of someone that strangely enough, was a semi-professional table-tennis player some years ago. We were at a friend's house that has a ping-pong (as we call it) table and we had a few semi-competitive games and a lot of laughs.
Among my friends and when I was young, I was always a rather good player, but a lot of my ability to win was based off of my rather "good" serving skills where I would make this sort of really fast serve that would barely make it over the net and then hit towards the back of the table on the other side. My opponents would normally play back on the receiving of the serve, and if they got too far back I would play it soft and barely have it go over the net.
I was using this serve just like I always have, the other night at my friend's house. The guy who was once a professional player kindly pointed out to me in private (I appreciated this discretion) that almost every single one of my serves would be considered illegal to people that really know the rules. lol

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I don't really watch the sport on TV or anything but I do recall kind of wondering why it is that none of the truly good people serve the same style of "rocket serve" that I do and well, as was pointed out to me by the visiting pro and later verified by looking it up, this is because you aren't allowed to serve like I do.

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According to the rules you must throw the ball straight up at least 16 cm from an open palm. For my "rocket serve" I was basically letting the ball fall just a tiny bit from my hand and then hitting the crap out of the ball. It turns out this is not allowed at all and if I were to throw the ball up 16cm my smash wouldn't work. The ball must be struck as it is falling, not on its way up. Now I don't think that my group of friends would ever enforce this but the point is that I have been doing it wildly illegally my entire life.
This wasn't the only thing I was doing that is against the rules though. I would soon find out my secondary serve of barely making the ball go over the net was also illegal.

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I don't know how it is that this was never pointed out to me but when you serve the ball you have to strike it initially BEHIND the table's end. On my "soft touch" serves where the ball would barely go over the net, I was normally striking it halfway up the table and this is not allowed at all. I honestly don't know how it is that I made it all of my life serving wildly against the rules and it was never pointed out by anyone.

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my alternate serve was also against the rules
I guess Americans maybe just don't take this sport seriously and it would be akin to me bowling in cricket against the rules. We don't really play the sport so I suppose it is understandable that we might not be doing it 100% accurately.
Something that in certain groups I was playing with that was enforced but actually is NOT a rule is that some people would say that you must serve into the opposite "box" across the table during service. As it turns out this is NOT true. You can serve the ball anywhere on the opposite side of the table and those boxes only exist as some sort of rule when playing doubles. Huh, I learned something!
Now this is a little devious of me but I don't think I am going to tell my friends about this because I will absolutely suck if required to play by these rules. Seeing as how I only play table tennis / ping-pong once or twice a year, I think that we can probably let it slide.