The Dvorak keyboard is a keyboard layout named after its designer, Dr. August Dvorak. He designed the keyboard as alternative to the standard QWERTY keyboard layout, with the goal of improving typing ergonomics.
Dvorak developed the new keyboard layout after studying common typing patterns. He determined the QWERTY layout, which was designed for telegraph operators and early typewriters, was inefficient. It required awkward motions, didn't use the home row (ASDF) enough, and required many common key patterns to be typed with one hand.
To improve typing efficiency, Dvorak designed his keyboard layout to alternate keystrokes between left and right hands. He also placed the most common letters in the home row. For example, since nearly all words have vowels, the home row on the Dvorak keyboard begins with the letters AOEUI. The vowel keys are placed next to each other since vowels often alternate with consonants.
Dvorak patented his keyboard layout in 1936, claiming layout offered the faster typing speeds, greater accuracy, and less fatigue than the QWERTY keyboard. Despite these benefits, the Dvorak keyboard has never achieved the popularity of the QWERTY layout. Most people still learn to type on a QWERTY keyboard and simply do not want to relearn a new keyboard layout. Therefore, nearly all desktop computers and laptops sold in Western countries come with QWERTY keyboards.
NOTE: The original version of the Dvorak keyboard is also known as the Dvorak Simplified Keyboard (DSK). In 1982, ANSI standardized a slight variation of the Dvorak keyboard layout, called the American Simplified Keyboard (ASK).