Progressive lenses are a type of multifocal eyeglasses that resemble single vision correction lenses that correct vision at all distances. As opposed to bifocals, which serve a similar purpose, progressive glasses are designed to correct at all distances without the stark, visible contrast in powers that distinguishes bifocals from other types of glasses. These types of lenses can be used only as progressive reading glasses or simply for everyday use. The power of progressive eyeglasses gradually changes along the surface of the lens, thereby correcting vision at virtually any distance. There are several types of progressive lenses, such as blue-light computer lenses or transition lenses, and the progressive lens price will vary depending on the type of lens and lens treatment desired.