[1][2] Invented by Charles Barbier as the tool for writing letters that could be read by touch,[3] the slate and stylus allow for a quick, easy, convenient and constant method of making embossed printing for Braille character encoding.[8][9] Braille with its slate and stylus was unique in that it was the first and, until computers with screen readers, the only method a blind person could write and read themselves what had been written.[10] The earliest systematic attempt to provide a method to "teach the blind to read and to write, and give them books printed by themselves" was by Valentin Haüy who used a system of embossed roman characters.One notable approach was that of Nicholas Saunderson (Lucasian Professor of Mathematics at Cambridge) blind nearly from birth, who devised an Arithmetical slate.It was successfully used at the Institution Royale des Jeunes Aveugles in Paris for several years, until Braille created his own system, which was more compact and flexible.
Six Principal Systems of Embossed Type;Haüy, Gall, Howe, Moon, Braille, Wait