I used to play with them over forty years ago. You have a deck of cards with a theme - say it's exotic cars. Each card has a picture (in this example of a make and model of car) and a set of categories with a number for each. In the case of cars, the categories might be: cost, length, weight, top speed, horsepower, number of cylinders.
You shuffle the cards and deal them out. When you play one person is the caller. The caller looks at the next card in her hand (she's not allowed to choose, she can only play the one from the top of her pile) and chooses one of the categories that she thinks that card might win in. Say she's looking at a Ferrari: it only has eight cylinders and is not very long or heavy, but it is fast, powerful, and does cost a lot of money. She decides to go for the speed category and announces, "one hundred and sixty five miles per hour." Now if the other players' top cards don't beat that speed then the caller wins that round and collects the top card from each of the other players' hands and adds them to the bottom of her own pile.
If one of the other players' cards beats your card for the chosen category, that winning player collects the cards and becomes the new caller. If there is a tie, then the cards are left in the centre and another round is played until someone wins and collects all the cards in the centre pile.
The game continues until one player has won all the cards.
Strategy consists of knowing which cards are best in which categories, and, near the end of the game, knowing which cards your opponent still holds (and the position too if you can count and remember the positions).
There are variations, of course. You can play to lose your cards, or there are versions where you are allowed to look at all your cards and decide which one to play next, but what I described is the normal game.
What are the categories for the Space and Dinosaur cards, Moose?
Jupiter would beat other (Solar System) planets on mass and diameter, but I suppose there are exo-planets and stars in the set too. I don't think the space set would be much good for playing the normal game. *shrug*
The "year of discovery", 1610, for Jupiter is plain wrong. Jupiter was known by the ancients. I suppose 1610 was the first time it was seen through a telescope so before then no one would have known it was stripey.
The ones I remember best were the original Dubreq ones, launched in 1978 according to Wikipedia. One of my friends had a few sets: cars, motorcycles, locomotives, ... I remember we enjoyed the exotic/sports cars sets the most.
The Rover SD1 was a pretty poor card to hold as it only had a small engine and wasn't very fast. Not really an exotic car and shouldn't have been in the pack. I think the best ploy with this card would be to announce the V8 engine, hope for a draw with other larger faster V8s and then win with your next card. Of course, if your opponent had a V12 then you'd lose - but most V12 cars would beat the SD1 in every other category too.