Progressive lenses have three prescriptions in one pair of glasses. That allows you to do close-up work (like reading a book), middle-distance work (like checking out a website on a computer), or distance viewing (like driving) without needing to change your glasses. They’re sometimes called multifocal lenses. Progressive lenses are an update on bifocal and trifocal lenses. Both of these more traditional types of glasses have telltale lines in the lenses. Progressives have a seamless look. Sometimes they’re called “no-line bifocals,” but that’s not quite right. It would be more accurate to call progressive lenses “no-line trifocals.