Since bread is square, why is sandwich meat round? Did Adam and Eve have navels? Why do they put Braille instructions and labels on drive-up ATM machines? Why don’t we have A and B-cell batteries, since we do have AAs, AAAs, Cs, Ds, and whatever those big blocky things are called? And why don’t 9-volt batteries have a letter designation, like all the others? What makes the Teflon stick to the pan? Answers to all of these--and more.