Chorded keyboard (a writing system for the blind) uses either 6 or 8 tactile 'points' from which all letters and numbers are formed. When Louis Braille invented it, it was produced with a needle holing successively all needed points in a cardboard sheet. In 1892, Frank Haven Hall, superintendent of the Illinois Institute for the Education of the Blind, created the Hall Braille Writer, which was like a typewriter with 6 keys, one for each dot in a braille cell. The Perkins Brailler, first manufactured in 1951, uses a 6-key chord keyboard (plus a spacebar) to produce braille output, and has been
Dot book Dot book A dot book (also dotbook or dot-book or drill book) is a small notebook utilized by marching bands (especially high school show bands and drum corps) in order to aid the learning of formations on a field. The dot book was invented by Leslie Allard, a prominent high school band instructor and all-star percussionist. The name is derived from the use of dots on drill sheets which symbolize players on the field: a dot book focuses on the owner's particular dots and other marchers the player may have to guide (use to determine an adjusted location). The general