A Support document on Apple.com reveals that OS X Mavericks includes support for a flurry of braille displays employed by the visually impaired to be able to use their Macs.
A refreshable braille display, or braille terminal (as they are sometimes referred to) is an electro-mechanical device which displays braille characters by using round-tipped pins that raise and then hide away. Blind computer users generally use a braille display to read text output.
According to Apple KB article HT5348, “OS X includes USB and Bluetooth drivers for braille displays that can be used with VoiceOver.”
The Mac maker provides a lengthy list of braille displays that are supported by OS X Mavericks, including numerous models from Alva, American Printing House for the Blind (APH), Baum, Deininger, Eurobraille, Freedom Scientific, HandyTech, Harpo, HIMS, HIMS / GW Micro, Humanware, KGS, MDV, Ninepoint Systems, Nippon Telesoft, Optelec, Papenmeier.