A: True folded cards ( Puzzlers ? ) These can be unfolded and worked out topographically.
B: Trick/Illusion cards ( Magicians ? )
I'm not sure about Olympic rings ( semicircles - if you look, only one intertwines all the others, which actually rest one on the other ). We need to see that one up close (without glass). Or look at the back.
All the one's I have posted could be examined and found to be just folded, apart from that last one, which would be in category B the way I made it. I haven't found a true fold method for that one.... ( I did destroy quite a few cards trying

No I haven't seen the swirlygig video, I will have a look, thanks for the tip...