Keyboard layoutA keyboard layout is any specific physical, visual or functional arrangement of the keys, legends, or key-meaning associations (respectively) of a computer keyboard, mobile phone, or other computer-controlled typographic keyboard. is the actual positioning of keys on a keyboard. is the arrangement of the legends (labels, markings, engravings) that appear on those keys. is the arrangement of the key-meaning association or keyboard mapping, determined in software, of all the keys of a keyboard; it is this (rather than the legends) that determines the actual response to a key press.
Binary black holeA binary black hole (BBH), or black hole binary, is a system consisting of two black holes in close orbit around each other. Like black holes themselves, binary black holes are often divided into stellar binary black holes, formed either as remnants of high-mass binary star systems or by dynamic processes and mutual capture; and binary supermassive black holes, believed to be a result of galactic mergers. For many years, proving the existence of binary black holes was made difficult because of the nature of black holes themselves and the limited means of detection available.
Dvorak keyboard layoutDvorak ˈdvɔːræk is a keyboard layout for English patented in 1936 by August Dvorak and his brother-in-law, William Dealey, as a faster and more ergonomic alternative to the QWERTY layout (the de facto standard keyboard layout). Dvorak proponents claim that it requires less finger motion and as a result reduces errors, increases typing speed, reduces repetitive strain injuries, or is simply more comfortable than QWERTY.