Flat-panel membrane keyboards are most often found on appliances like microwave ovens or photocopiers. A common design consists of three layers. The top layer has the labels printed on its front and conductive stripes printed on the back. Under this it has a spacer layer, which holds the front and back layer apart so that they do not normally make electrical contact. The back layer has conductive stripes printed perpendicularly to those of the front layer. When placed together, the stripes form a grid. When the user pushes down at a particular position, their finger pushes the front layer down through the spacer layer to close a circuit at one of the intersections of the grid. This indicates to the computer or keyboard control processor that a particular button has been pressed.
A Bluetooth keyboard is a wireless keyboard that connects and communicates with its parent device via the Bluetooth protocol. These devices are widely used with such portable devices as smart phones and tablets, though they are also used with laptops and ultrabooks. Bluetooth keyboards became popular in 2011, coincident with the popularity of portable devices.
Devanagari InScript bilingual keyboard layout has a common layout for all the Indian scripts. Most Indic scripts have the same phonetic character order. A person who knows InScript typing in one script can type in any other Indic script using dictation even without knowledge of that script.
Most bluetooth keyboards have standard qwerty layouts, though some mini bluetooth keyboards may have a different layout. Bluetooth keyboards are compatible with all the leading operating systems such as Android, iOS, Linux, macOS, and Windows. Since they are used primarily for portable devices bluetooth keyboards have special function keys for Android and iOS operating systems. Most bluetooth keyboards, except a few, are not compatible across operating systems, so compatibility of the keyboard needs to be checked before purchasing one; this is because of the special function keys which differ between Android and iOS.
The IBM Model F keyboard is mechanical-key design consisted of a buckling spring over a capacitive PCB, similarly to the later Model M keyboard that used a membrane in place of the PCB.
Along with the UZT keyboards, phonetic keyboards have been developed for Urdu. Phonetic keyboards works with the sound of the words, e.g. 'a' button of the English keyboard contain an Urdu word which is similar to the sound of 'a' and same is the case for other characters. Though less common in the past, phonetic keyboards have seen wider use recently. CRULP (Center for research for Urdu language processing) has been working on phonetic keyboard designs for URDU and other local languages of Pakistan. Their CRULP Urdu Phonetic Keyboard Layout v1.1 for Windows is widely used and considered as a standard for typing Urdu on Microsoft platform. However it has not been adopted by Microsoft for any Windows platform.
Further, the keyboard size depends on the extent to which a system is used where a single action is produced by a combination of subsequent or simultaneous keystrokes (with modifier keys), or multiple pressing of a single key. A keyboard with few keys is called a keypad.
One factor determining the size of a keyboard is the presence of duplicate keys, such as a separate numeric keyboard or two each of Shift, ALT and CTL for convenience.
The action of a keyboard is the internal mechanism by which the keys work in order to move and produce sound, or, in this case, MIDI data. Two major types of keyboard actions exist: those derived from traditional, European, key-based instruments and non-traditional, contemporary designs that allow for expanded playing possibilities.
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.
Another factor determining the size of a keyboard is the size and spacing of the keys. The reduction is limited by the practical consideration that the keys must be large enough to be easily pressed by fingers. Alternatively, a tool is used for pressing small keys.
In live performances, multiple electronic keyboards could be played together at one time, each by one musician, forming a keyboard ensemble. Keyboard ensembles are mostly performed within a band on an elaborate stage, while some can even serve as a simpler substitute to the more conventional orchestra, replacing stringed and wind instruments.
The typing loads between hands differs for each of the keyboard layouts. On QWERTY keyboards, 56% of the typing strokes are done by the left hand. As the right hand is dominant for the majority of people, the Dvorak keyboard puts the more often used keys on the right hand side, thereby having 56% of the typing strokes done by the right hand.
Introduced and included with the original Macintosh in 1984, it debuted with neither arrow keys to control the cursor nor an integrated numeric keypad. It used a telephone cord-style RJ-10 connector to the case (also used with the Amstrad PCW series of computers). The keyboard pinouts are "crossed" so it isn't possible to use a standard telephone cord as a replacement; doing so will result in damage to the keyboard or the computer. The keyboard also introduced a unique command key similar to the "open" Apple Key on the Lisa.
An optical virtual keyboard was invented and patented by IBM engineers in 1992. It optically detects and analyses human hand and finger motions and interprets them as operations on a physically non-existent input device like a surface having painted keys. In that way it allows to emulate unlimited types of manually operated input devices such as a mouse or keyboard. All mechanical input units can be replaced by such virtual devices, optimized for the current application and for the user's physiology maintaining speed, simplicity and unambiguity of manual data input.
On computers running Windows, Alt-Shift switches between keyboard layouts. Holding down a Shift key (or pressing Caps Lock) in Windows produces the uppercase Latin letter without the need to switch layouts.
Each key on a mechanical-switch keyboard contains a complete switch underneath. Each switch is composed of a housing, a spring, and a stem, and sometimes other parts such as a separate tactile leaf or a clickbar. Switches come in three variants: linear with consistent resistance; tactile with a non-audible bump; and clicky, a tactile with an audible click. Depending on the resistance of the spring, the key requires different amounts of pressure to actuate and to bottom out. The shape of the stem as well as the design of the switch housing varies the actuation distance and travel distance of the switch. The amount of sound produced by actuation can also be changed by the addition of rubber dampeners. Like other types of keyboards, mechanical keyboards allow for the removal and replacement of keycaps, but replacing them is more common with mechanical keyboards due to common stem shapes.
The specialist DataHand keyboard uses optical technology to sense keypresses with a single light beam and sensor per key. The keys are held in their rest position by magnets; when the magnetic force is overcome to press a key, the optical path is unblocked and the keypress is registered.
In the mid-90's Apple released the Apple Newton sub-mini keyboard to allow a quick input alternative to the Newton's handwriting recognition, which required extensive training to become useful. It connected via the Newton's serial interface. Many Mac users favoring the portable size were able to use it on a Mac utilizing a third-party enabler. Like the iPhone that would come 10 years later, the Newton also included a virtual keyboard.