They're challenging, baffling, and wildly entertaining: here are 240 colorful, mind-boggling puzzles of every kind to sharpen anyone's thinking skills! Vivid optical illusions fool and tease the eye: try to find both a young girl and her grandmother in what seems to be a picture of only one woman. Or test those smarts on a different type of visual problem by figuring out which of six pieces isn't needed to make a cube.