Euchre. (Euchre? I don't even know her! - eh, sorry.)
The 'rents are from upstate New York (helllloooooo Rochester!) and this was a game that I watched the adults play growing up. I was always fascinated by this fast paced 5-card game. My dad, grandpa, and two uncles would sit down and "throw cards". Children were not allowed to play at the men's table, and you could only stay if you didn't talk during the hand.
They would deal 'em out: 3-2, 3-2 then 2-3, 2-3, flip the top card on the kitty, growl out their bids and then let fly. Dad would lead and then 3 more cards would appear almost simultaneously on the table. Uncle Dave would lead and then swish! swish! swish! One more round of that and then they'd all throw their cards in.
I was left bewildered. Hey, aren't there two more tricks to play? No point. They got a "stopper". Take your point and shuffle 'em and deal again. It was fast and furious and almost like a secret society with its own language. One had to be an Initiate to follow the game. I'm still surprised at how much of the jargon I absorbed without realizing it. Going alone. Dutch point (Dutchman), Left Guarded, sandbagging, never-send-a-baby-for-beer, etc.
I loved it. I still do. I like to play when I can find enough people outside my family who know the game. It's a fast trump game, but not as complicated as Bridge (which I still don't get), and not as nasty as Hearts or Spades. Pinochle is another favorite but involves multiple decks of cards.
Oh, and for the record, "real" counters are with 2's and 3's, not 6's and 4's! (Yes, that's a religious debate.)