Key limes are smaller and sweeter than regular limes, and they are grown in the Florida Keys. They also have less pith (the bitter white part in the peel). To make sure you get the same great taste with regular limes, make sure you don't squeeze the limes too hard, otherwise you will also extract undesirable bitter flavors from the pith. A tip for squeezing limes to get the most juice: roll the lime under your palm over the countertop to burst the juice-containing cells and make it easier for the juice to come out.