History
The base of a refreshable braille display is a pure braille terminal. There, the input is performed by two sets of three keys plus a space bar (as in the Perkins Brailler), while output is via a refreshable braille display consisting of a row of electromechanical character cells, each of which can raise or lower a combination of six (or in some cases, eight) round-tipped pins. Other variants exist that use a conventional QWERTY keyboard for input and braille pins for output, as well as input-only and output-only devices. In 1951, David Abraham, a woodworking teacher at Perkins, created a portable braille terminal.
Read more about this topic: Refreshable Braille Display
Famous quotes containing the word history:
“History does nothing; it does not possess immense riches, it does not fight battles. It is men, real, living, who do all this.... It is not “history” which uses men as a means of achieving—as if it were an individual person—its own ends. History is nothing but the activity of men in pursuit of their ends.”
—Karl Marx (1818–1883)
“History is more or less bunk. It’s tradition. We don’t want tradition. We want to live in the present and the only history that is worth a tinker’s damn is the history we make today.”
—Henry Ford (1863–1947)
“It is remarkable how closely the history of the apple tree is connected with that of man.”
—Henry David Thoreau (1817–1862)