The primary input device on most computers (with all due respect to the mouse) is the QWERTY keyboard. This situation is deplorable and pathetic; fortunately, it can be significantly improved with minimal modification.
The QWERTY key layout, or key map, is especially awkward and deficient in many ways. The Dvorak key map is better in many ways, but it also has problems.
Changing the arrangement of keys certainly helps, and I recommend the Colemak key map which is very similar to QWERTY (keys for many common shortcuts remain in the same location), yet it is also more efficient than Dvorak. You can compare them with your own prose.
If one is adept with QWERTY, then learning a new layout may be initially frustrating. In any case, I have found Colemak to be a significant improvement even without touch typing (essentially, any layout which maps the most frequently used characters to the home row likely provides similar advantage; i.e., less hunting, more pecking).
Common keyboards have staggered rows just like the crude mechanical typewriters1 from whence they came; the key spacing is defined by an array of long since deceased hammers whose ghosts continue to haunt human hands. Ironically, even most so-called «ergonomic» keyboards persist with this staggered arrangement. Here are some honestly ergonomic keyboards:
I must say, the Blickensderfer is one typewriter that wins my respect. ↩