Computer keyboard - Wikipedia. Typing on a computer keyboard. In computing, a computer keyboard is a typewriter- style device which uses an arrangement of buttons or keys to act as a mechanical lever or electronic switch. Following the decline of punch cards and paper tape, interaction via teleprinter- style keyboards became the main input device for computers. A keyboard typically has characters engraved or printed on the keys (buttons) and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous key presses can produce actions or execute computer commands. Despite the development of alternative input devices, such as the mouse, touchscreen, pen devices, character recognition and voice recognition, the keyboard remains the most commonly used device for direct (human) input of alphanumeric data into computers. In normal usage, the keyboard is used as a text entry interface to type text and numbers into a word processor, text editor or other programs. In a modern computer, the interpretation of key presses is generally left to the software. A computer keyboard distinguishes each physical key from every other and reports all key presses to the controlling software. Keyboards are also used for computer gaming, either with regular keyboards or by using keyboards with special gaming features, which can expedite frequently used keystroke combinations. A keyboard is also used to give commands to the operating system of a computer, such as Windows' Control- Alt- Delete combination, which brings up a task window or shuts down the machine. A command- line interface is a type of user interface operated entirely through a keyboard, or another device doing the job of one. History. It was through such devices that modern computer keyboards inherited their layouts. As early as the 1. The teleprinter, in its more contemporary form, was developed from 1. American mechanical engineer Charles Krum and his son Howard, with early contributions by electrical engineer Frank Pearne. If your keyboard keys are not working the way they should be, then you may want to restore or reset Keyboard keys to default settings in Windows 10/8/7.Earlier models were developed separately by individuals such as Royal Earl House and Frederick G. Creed. Earlier, Herman Hollerith developed the first keypunch devices, which soon evolved to include keys for text and number entry akin to normal typewriters by the 1. The development of the earliest computers incorporated electric typewriter keyboards: the development of the ENIAC computer incorporated a keypunch device as both the input and paper- based output device, while the BINAC computer also made use of an electromechanically controlled typewriter for both data entry onto magnetic tape (instead of paper) and data output. From the 1. 94. 0s until the late 1. Because of the limitations of terminals based upon printed text in comparison to the growth in data storage, processing and transmission, a general move toward video- based computer terminals was effected by the 1. Datapoint 3. 30. 0 in 1. The keyboard remained the primary, most integrated computer peripheral well into the era of personal computing until the introduction of the mouse as a consumer device in 1. By this time, text- only user interfaces with sparse graphics gave way to comparatively graphics- rich icons on screen. However, keyboards remain central to human- computer interaction to the present, even as mobile personal computing devices such as smartphones and tablets adapt the keyboard as an optional virtual, touchscreen- based means of data entry. Keyboard types. A keyboard with few keys is called a keypad. Early Version Download: To type Khmer fonts on the web, download the following: MS-Windows Khmer Fonts Package: File size ~141k; Keyboard Template: File size ~150k. See also text entry interface. Another factor determining the size of a keyboard is the size and spacing of the keys. 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. Standard. Desktop computer keyboards, such as the 1. US traditional keyboards or the 1. Windows keyboards, include alphabetic characters, punctuation symbols, numbers and a variety of function keys. The internationally common 1. Z or Y). Also the enter key is usually shaped differently. Computer keyboards are similar to electric- typewriter keyboards but contain additional keys, such as the command or Windows keys. There is no standard computer keyboard, although many manufacture imitate the keyboard of PCs. There are actually three different PC keyboard: the original PC keyboard with 8. AT keyboard also with 8. Keyboard setup for macrons. A macron is a line above a vowel to indicate that it should be spoken as a long vowel: If you are currently running Windows Vista as your primary operating system, we can use its built-in tools to modify your hard drive partitions. How to Reset a Keyboard. If your keyboard stops displaying the right characters, or not all the keystrokes are being registered, you may need to reset your keyboard. Windows 7 or Vista. How to Implement the Korean Keyboard Option (in Windows 7 or Vista) 1) Open the Control Panel. 2) Select “Clock, Language and Region”. How to use Keyboard Layout section of Control Panel to activate Russian keyboard for Windows 7,8,10/Vista and XP/2003. This page is a part of my site's Chapter. The three differ somewhat in the placement of function keys, the control keys, the return key, and the shift key. Laptop- size. They may not have a numerical keypad, and the function keys may be placed in locations that differ from their placement on a standard, full- sized keyboard. The switch mechanism for a laptop keyboard is more likely to be a scissor switch than a rubber dome; this is opposite the trend for full- size keyboards. Flexible keyboards. Additionally, the flexibility allows the user to fold/roll the keyboard for better storage and transfer. However, for typing the keyboard must be resting on a hard surface. The vast majority of flexible keyboards in the market are made from silicone; this material makes them water and dust proof, a very pleasant feature especially in hospitals where keyboards are subjected to frequent washing. For connection with the computer the keyboards use a USB cable, and operating system support reaches as far back as Windows 2. Handheld. Typically handheld keyboards hold all the alphanumeric keys and symbols that a standard keyboard would have, yet only be accessed by pressing two sets of keys at once; one acting as a function key similar to a 'Shift' key that would allow for capital letters on a standard keyboard. Small keyboards are also useful where there is a limited workspace. A thumb keyboard (thumb board) is used in some personal digital assistants such as the Palm Treo and Black. Berry and some Ultra- Mobile PCs such as the OQO. Numeric keyboards contain only numbers, mathematical symbols for addition, subtraction, multiplication, and division, a decimal point, and several function keys. They are often used to facilitate data entry with smaller keyboards that do not have a numeric keypad, commonly those of laptop computers. These keys are collectively known as a numeric pad, numeric keys, or a numeric keypad, and it can consist of the following types of keys: Arithmetic operators, numbers, arrow keys, Navigation keys, Num Lock and Enter key. Multifunctional. Many are programmable, configurable computer keyboards and some control multiple PCs, workstations (incl. SUN) and other information sources (incl. Thomson Reuters FXT/Eikon, Bloomberg, EBS, etc.) usually in multi- screen work environments. Users have additional key functions as well as the standard functions and can typically use a single keyboard and mouse to access multiple sources. New generation multifunctional keyboards feature a touchscreen display to stream video, control audio visual media and alarms, execute application inputs, configure individual desktop environments, etc. Multifunctional keyboards may also permit users to share access to PCs and other information sources. Multiple interfaces (serial, USB, audio, Ethernet, etc.) are used to integrate external devices. Some multifunctional keyboards are also used to directly and intuitively control video walls. Common environments for multifunctional keyboards are complex, high- performance workplaces for financial traders and control room operators (emergency services, security, air traffic management; industry, utilities management, etc.). Non- standard layout and special- use types. Since there are many combinations available, chorded keyboards can effectively produce more actions on a board with fewer keys. Court reporters' stenotype machines use chorded keyboards to enable them to enter text much faster by typing a syllable with each stroke instead of one letter at a time. The fastest typists (as of 2. Some chorded keyboards are also made for use in situations where fewer keys are preferable, such as on devices that can be used with only one hand, and on small mobile devices that don't have room for larger keyboards. Chorded keyboards are less desirable in many cases because it usually takes practice and memorization of the combinations to become proficient. Software. Another input device such as a mouse or a touchscreen can be used to operate each virtual key to enter text. Software keyboards have become very popular in touchscreen enabled cell phones, due to the additional cost and space requirements of other types of hardware keyboards. Microsoft Windows, Mac OS X, and some varieties of Linux include on- screen keyboards that can be controlled with the mouse. In software keyboards, the mouse has to be maneuvered onto the on- screen letters given by the software. On the click of a letter, the software writes the respective letter on the respective spot. Projection. The device then uses a camera or infrared sensor to . Projection keyboards can simulate a full size keyboard from a very small projector. Because the . Users of projected keyboards often experience increased discomfort in their fingertips because of the lack of . A flat, non- reflective surface is also required for the keys to be projected. Most projection keyboards are made for use with PDAs and smartphones due to their small form factor. Optical keyboard technology. Most commonly the emitters and sensors are located in the perimeter, mounted on a small PCB. The light is directed from side to side of the keyboard interior and it can only be blocked by the actuated keys. Most optical keyboards require at least 2 beams (most commonly vertical beam and horizontal beam) to determine the actuated key.
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