Its unique name is because the paper was watermarked with the symbol of a joker with a fool's cap and bells. It's slightly bigger than an A4 sheet
In the middle ages, contracts were drawn upon a large sheet of paper, & both parties signed. (1/🧶)
Credit: Micheal Miller, tinyurl.com/y2oyq6xl
Just ask anyone who has had to sign 100s of pages of contracts during an M&A.
(1) Leegality, leegality.com, which is taking the "paper" out of paperwork (caveat: fren works here);
(2) SignEasy, signeasy.com
Do feel free to include other names below