Serial plotter shows changing values when moving near/away from board

Even with no components on the board, I noticed that if i'm using the serial plotter to monitor my Arduino, I can make the values change by moving my hands towards and away from the board.

How does this work? Am I affecting magnetic fields when moving?

"the values change" - what values? Are you confused by floating analog inputs?

[ and why do you imagine you are magnetic? ]

ok, I found out from IRC that human bodies can exert an influence over EM fields, which is what one of my floating analog inputs were picking up whenever I moved closer to the board!