Progressive or No-Line: A multifocal with many focal areas to give you a smooth transition from near to far with no lines separating the areas.
Flat-top Bifocal: Provides two focus areas for vision at two different distances. Has a line separating the areas of focus.
Trifocals: Provides three focus areas for vision at three different distances. Two lines separate the areas.
Occupational: Lenses designed for special needs. May be like any of the above or with other features, such as a bifocal segment at the top of your glasses, computer lenses, safety or special distances.
Single-Vision: All purpose or designed for specific visual needs.