A "fixed-split keyboard" is a single board, with the keys separated into two or three groups, allowing the user to type at a different angle than the typical straight keyboard.
An "adjustable split keyboard" has the keyboard split into several independent pieces, so the angle between them can be easily changed. Either of these types of keyboards may include elevated sections at various angles.
Other ergonomic keyboards have fixed, vertically aligned keys, so the user types with their hands perpendicular to the ground, thumbs-up. Still others allow a range of rotation and elevations. A few ergonomic keyboards do not have the typical one key per letter, such as a keyer or a keyless ergonomic keyboard. Datahand eliminates the need for any wrist motion or finger extension.
Simple ergonomic keyboards can cost as little as typical keyboards or as much as $600 for high end keyboards
An ergonomic keyboard may reduce muscle strain and reduce risk of Carpal Tunnel syndrome, but there is no clear evidence of benefit. After a user takes the time to adjust to this style of keyboard, these keyboards can make typing easier, faster and less awkward.
Some ergonomic keyboards are highly priced, though not necessarily so. They may take a little practice to get used to, and many people don't want to go to the trouble of adjusting. These keyboards may take more space on your computer table and force the mouse to be farther away.