Floating Woman – What It is
While performing the floating woman act, the magician will either call a woman from the audience or take someone who they have already prepared for the show. They begin by asking the woman to lie down on a board that has been kept in place by two chairs. Slowly, they take the two chairs away, which should normally make the woman fall down, but instead, she stays perfectly placed on the table that is suspended in the air. Some magicians even run a metal hoop along the body of the woman to prove that no cables are holding her up.
Source: Reddit
Random magic fact: At the 1988 magic championships, a magician was ultimately disqualified because his performance was so amazing that the other magician judges thought he must have been cheating. He performed the exact same act three years later, (letting the judges shuffle the cards) and he still won.