QWERTY is a well established standard for how the keys on a keyboard are placed. It is almost universally accepted, most countries use it with only minor modifications to allow for any additional letters. However, it is far from optimal. It is even said that QWERTY was purposefully designed to slow down the typist, in order to protect the early typewriters.
Modern research has shown that large speedups in typing can be obtained by designing a new keyboard radically different from the current standard. Specifically, it should be split in two, and characters should be entered by pressing several keys at once.
However, some small speedups can be obtained simply by remapping the keys using the same physical layout. The Dvorak layout is an example of this. It is usually not worth the frustration of having to master a two different keyboard layout, but some people have made the effort.
With keyboard-mode you can use QWERTY layout on a Dvorak
keyboard, or vice versa. Simply type M-x keyboard-query-mapping,
select the "language" `Keyboard Layout', and specify the layout
on the keyboard, and what layout you want on the screen. Answer n
when it ask you about pressing the key twice to get the original
binding. You can then switch between QWERTY and Dvorak with M-x
keyboard-mode.
See section Support for the Scandinavian Languages for a more detailed descriptions of these functions.