This is an optical illusion created by Chukyo University professor Kohske Takahashi featuring a bunch of identical repeating sine waves that appear to be even more curvy like macaroni or very angular, depending on their shading. Cool I guess, but my eyes really don't appreciate tricks being played on them. My nose either. One of my friends bought me one of those trick candles that starts smelling like lilacs but then fades to farts. It took me a while to figure it out, but less than fifteen minutes to drive to his house and throw it through a window.
Keep going for a shot of two sets of lines superimposed on each other to show they're identical, despite what your brain might be telling you (mine's telling me to steal a coworker's lunch!).
Thanks to Jacques W, who agrees his brain never asked for this.