What is Retina?

Retina, in the context of technology, most commonly refers to Apple's brand name for high-pixel-density displays. These displays have a pixel density high enough that the human eye is unable to distinguish individual pixels at a typical viewing distance. This results in sharper images and text. Retina displays are used in a variety of Apple products, including iPhones, iPads, MacBooks, and iMacs. While Apple popularized the term, the underlying technology of high-resolution displays is used by other manufacturers as well, often under different marketing names.