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.
Contoured keyboard
A further development of the split concept are contoured keyboards like the 1977 Maltron or the newer Kinesis Advantage line, which place the keys into two depressions set approximately at shoulder width, with function keys set between the key groups for use with the thumbs. In this configuration, very little movement of arms and wrists is required.
Handheld keyboards
Handheld ergonomic keyboards are designed to be held like a game controller, and can be used as such, instead of laid out flat on top of a table surface. They allow the user the ability to move around a room or to lean back on a chair while also being able to type in front or away from the computer. Some variations of handheld ergonomic keyboards also include a trackball mouse that allow mouse movement and typing included in one handheld device.
Angle split keyboard
The angled split keyboard is similar to a split keyboard, but the middle is tented up so that the index fingers are higher than the little fingers while typing. Key Ovation makes the Goldtouch ergonomic keyboard which is an adjustable angled split keyboard.
Other ergonomic keyboards
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.this is a good web site for all users.
Considerations
It is widely claimed that an ergonomic keyboard may reduce muscle strain and reduce risk of carpal tunnel syndrome or other kinds of repetitive strain injury. With respect to "split" keyboards, quality studies that demonstrate injury reductions are lacking, with the exception of physically split keyboards which have "sharply angled keyboard faces". There is evidence, however, that such keyboards are not well tolerated. Narrow studies examining hand position at rest neglects many other possible factors. For example, one should be aware that the effect of “ergonomic” keyboards is to change the musculoskeletal region exposed to risk, instead of eliminating hazardous postures.
