"Free keyboard layouts - called Dvorak layouts - are available for people who type with one hand or finger. These layouts make the most frequently typed characters on a keyboard more accessible to people who have difficulty using the standard keyboard layout (called the "QWERTY" layout).
Dvorak keyboard layouts reduce the amount of motion required to type common English text. Use of these layouts may also help avoid some types of repetitive strain injuries associated with typing.
Studies have also shown an increase in typing speed and accuracy when using the Dvorak layout for two hands. The left-hand or right-hand keyboard layouts can also be useful for people who type with a wand."
You do not need to modify your hardware keyboard to use these layouts, but you will need to change your keyboard settings to use the Dvorak layouts.
(A keyboard layout is a map or a definition of how keys are laid out on your keyboard. The keyboard layout you use is determined by software in your computer. The letters on your keys indicate the standard layout for your keyboard.)