Monday, October 14, 2019
Introduction To Computer Components Computer Science Essay
Introduction To Computer Components Computer Science Essay A keyboard is a computer hardware input device. keyboard is similar to the mechanical typewriter design, if we compare to keyboard with other computer hardware it is technological advance.New ergonomic keyboards can cost as much as a central processing unit or quality computer monitor. Instead of mouse the keyboard is often the principal input device on home and office computers.the basic functions of keyboards are it is used for text input,keyboards are also used to precise image, interface manipulation such as sending special commands to the operating system even controlling characters and objects in computer games. Due to advance technology now adays some keyboards includes other input and output devicessuch as card reader,usb ports or integrated trackballs. Although there are pseudo-standards regarding key arrangement, the manufacturer of keyboards are free to create original arrangements and designs. While most keyboards intended for use in English-language environments use the QWERTY layout, many keyboards are available with alternative layouts such as Dvorak. Some specialty keyboards have two or more layouts or languages printed on the keys, while others have no layout printed at all. The blank keyboards are designed for a specific purpose such as this can be use by the touch typists only, who have no need to look at the keyboard while entering informationà ¢Ã¢â ¬Ã ¦..till here Most conventional keyboards are built using dome-membrane technology. In these models, keys are mounted on a tray which affords them up and down movement only. The keys are supported in the up position by rubber membrane domes on which they rest. The domes are easily collapsible, and quickly return to their upright positions when released from the collapsing force. The underside of each dome houses a graphite bullet, which completes an open circuit underneath the dome when the dome is collapsed. Special circuitry senses the completed circuit, and translates this to a key press which is then transmitted to the computer. Complex circuitry grids and patterns allow most keyboards to support over one hundred different keys with only about two dozen different circuits. In fact, careful layout of specific meta keys allows two- and even three- key-press combinations to be registered. More complex key-press combinations require very specialized circuitry, which few keyboards today support. Special features of the keyboard include: Numeric keypad: In numeric keypad is a portion in keyboard whichs allows to use keyboard like a calcuclator and input numbers into application program.it has an option of numlock key when this key has been pressed it activates the portion of the keyboard so that numbers can be entered in the computer. When the num lock key is not on, there are arrow keys on the keyboard which then work to move the cursor in different directions. The NUM LOCK key is a toggle key which switches back and forth between these two modes. Caps Lock: The CAP LOCKS key works in this same manner as the NUM LOCK key. If the Caps Lock is pressed on the keyboard whatever alphabets type from keyboard will type only in capital letters. If the Cap Lock light is not lit it will type only in small letters. Function Keys: The function keys are used to initiate commands on help menus or database programs especially before the development and use of computer pointing devices. They are still used extensively today as options on the keyboard to pull down menus or to be programmed to do specific functions in application programs. Ctrl or Shift keys also work with Function keys to add more commands to programs and what are called shortcuts, ways to operate functions like saving and deleting without going through elaborate features and steps. Short cuts speed up typing and input into the computer. Escape Key: One of the most important keys is the escape key. It usually use to cancel the command or to takes you back to the previous step ina a program. Main Types Of Keyboard: Keyboards are available in various shapes and sizes . they can be large and small almost like a custom car. They come in various colours and can be designed specifically for the user especially in a case of disabledà ¢Ã¢â ¬Ã ¦done QWERTY: The most popular is the standard QWERTY keyboard. The newer keyboards can have a trackball built into the keyboard. This allows the user the convenience of a built in pointing device. The trackball acts as the mouse and saves time and space in the work area. Ergonomic: This keyboard is built so that the keyboard is divided into two parts. One half fits the right hand and the other half fits the left hand. This split keyboard arrangement is built to fit the natural positioning of the hand and to help with repetitive motion hand injury which occurs when a job is carried out over and over again, such as in keyboarding. History of the Computerà Keyboard Keyboarding has 2 references nowadays; the first being typing with an alpha-numeric keyboard or typewriter, and the second of playing a piano, organ, or electronic keyboard. Keyboarding (typing) started in form with the invention of the Printing Press in the 1600s. Manual typewriters came some time later (with the keyboard layout of letters that we are accustomed to now). Additionally, there was another simple form of mono-keyboarding in electronic for with the advent of the telegraph (developed by Samuel Morse Morse Code) wherein a series of dots and dashes created letters, which spelled out words, which then composed a telegram to someone. There is another niche of keyboarding, which involves a courtroom recorder using a stenography machine. This machine has less character than a standard keyboard, and involves a system of shorthand in conjunction with fewer keys. A good example of shorthand is the use of abbreviations, such as Mfr stands for manufacturer. The invention of the computer keyboard begins with the typewriter The invention of the modern computer keyboard began with the invention of theà typewriter. Christopher Latham Sholes patented the typewriter that we commonly use today in 1868. The Remington Company mass marketed the first typewriters starting in 1877. Sholes and Glidden Type-writer: The first typewriter to be commercially successful was invented in 1867 by C. Latham Sholes, Carlos Glidden and Samuel W. Soule in Milwaukee, Wisconsin, although Sholes soon disowned the machine and refused to use, or even to recommend it. The working prototype was made by the machinist Matthias Schwalbach. The patent (US 79,265) was sold for $12,000 to Dens more and Yost, who made an agreement with E. Remington and Sons (then famous as a manufacturer of sewing machines) to commercialize the machine as the Sholes and Glidden Type-Writer. This was the origin of the term typewriter. Remington began production of its first typewriter on March 1, 1873, in Ilion, New York. It had a QWERTY keyboard layout, which because of the machines success, was slowly adopted by other typewriter manufacturers. Because the type bars of this typewriter strike upwards, the typist could not have seen characters as they were typed. This was the case in most early keyboard typ ewriters, however, as the type bars struck upward against the bottom of the platen and what was typed was not visible until a carriage return caused it to scroll into view. The difficulty with any other arrangement was ensuring that the type bars fell back into place reliably when the key was released. This was eventually achieved with various ingenious mechanical designs and so-called visible typewriters, such as the Oliver typewriter, were introduced in 1895. The older style continued in production to as late as 1915. Inventions Leading to the Computer Keyboard A few key technological developments created the transition of the typewriter into the computer keyboard. The teletype machine, introduced in the 1930s, combined the technology of the typewriter (used as an input and a printing device) with theà telegraph. Elsewhere, punched card systems were combined with typewriters to create what was called keypunches. Keypunches were the basis of early adding machines and IBM was selling over one million dollars worth of adding machines in 1931. Early computer keyboards were first adapted from theà punch cardà and teletype technologies. In 1946, theà Eniac computerà used a punched card reader as its input and output device. In 1948, the Binac computer used an electromechanically controlled typewriter to both input data directly onto magnetic tape (for feeding the computer data) and to print results. The emerging electric typewriter further improved the technological marriage between the typewriter and the computer. Typewriter/printer hybrids: Towards the end of the commercial popularity of typewriters in the 1980s, a number of hybrid designs combining features of printers were introduced. These often incorporated keyboards from existing models of typewriters and printing mechanisms of dot-matrix printers. The generation of teletypes with impact pin-based printing engines was not adequate for the demanding quality required for typed output, and alternative thermal transfer technologies used in thermal label printers had become technically feasible for typewriters. IBM produced a series of typewriters called Thermotronic with letter-quality output and correcting tape along with printers tagged Quiet writer. Brother extended the life of their typewriter product line with similar products. DEC meanwhile had the DECwriter. The development of these proprietary printing engines provided the vendors with exclusive markets in consumable ribbons and the ability to use standardized printing engines with varying degrees of electronic and software sophistication to develop product lines. Although these changes reduced prices and greatly increased the convenience of typewriters, the technological disruption posed by word processors left these improvements with only a short-term low-end market. To extend the life of these products, many examples were provided with communication ports to connect them to computers as printers. The increasing dominance of personal computers, desktop publishing, the introduction of low-cost, truly high-quality, laser and inkj et printer technologies, and the pervasive use of web publishing, e-mail and other electronic communication techniques have largely replaced typewriters in the United States. Typewriter erasers: The traditional erasing method involved the use of a special typewriter eraser made of hard rubber that contained an abrasive material. Some were thin, flat disks, pink or gray, approximately 2 inches (51 mm) in diameter by 1à ¢Ã ââ¬Å¾8 inches (3.2 mm) thick, with a brush attached from the center, while others looked like pink pencils, with a sharpen able eraser at the lead end and a stiff nylon brush at the other end. Either way, these tools made possible erasure of individual typed letters. Business letters were typed on heavyweight, high-rag-content bond paper, not merely to provide a luxurious appearance, but also to stand up to erasure. Typewriter eraser brushes were necessary for clearing eraser crumbs and paper dust, and using the brush properly was an important element of typewriting skill; if erasure detritus fell into the typewriter, a small buildup could cause the type bars to jam in their narrow supporting grooves Computer Keyboards Send Direct Electronic Impulses Earlier computer keyboards had been based either on teletype machines or keypunches. There were many electromechanical steps in transmitting data between the keyboard and the computer that slowed things down. With VDT technology and electric keyboards, the keyboards keys could now send electronic impulses directly to the computer and save time. By the late 70s and early 80s, all computers used electronic keyboards and VDTs. Nevertheless, the layout of the computer keyboard still owes its origin to the inventor of the first typewriter, Christopher Latham Sholes who also invented the QWERTY layout. However, the computer keyboard does have a few extra function keys. Present Keyboard technologies Solar Keyboard: Two solar panels at the top of the keyboard work to keep the internal battery charged, even in low indoor ambient light. When I took it out of the box, the battery was more than 50 percent charged after spending just 15 minutes in direct sunlight. After dark, the light from a 100-watt overhead bulb was able maintain the charge. The thing is anorexic when it comes to power consumption Wireless keyboard: (With Bluetooth Device) The Apple Wireless Keyboard is a wireless keyboard built for Macintosh computers and the iPad. It interacts over Bluetooth wireless technology and unlike its wired version, it has no USB connectors or ports. Both generations have low-power features when not in use. Bluetooth Laser Virtual Keyboard This is tiny device laser-projects a keyboard on any flat surface, it can type away accompanied by simulated key click sounds. It really is true future magic at its best. With 63 keys and and full size QWERTY layout the Laser Virtual Keyboard can approach typing speeds of a standard keyboard. in a size a little larger than a matchbook. Gaming Keyboard When it comes to video game input devices, the keyboard is probably the furthest from ideal. Lets face it, keyboards were not designed to serve as game peripherals. However, PC gamers have bent their gaming habits to fit the restrictions of the standard keyboard for so many years that most prefer keyboard controls to a gamepad. The WASD control scheme for shooters has long been the default but as games have become more complex shooters especially the need for quick access to the surrounding keys has become more and more evident. Hardware manufacturers recognized the need for faster, smoother and more-precise mice as gaming became more popular and many felt they could improve on the keyboard design as well. The problem is that the keyboard is not a finesse device. Either the keys are there or they arent and either you can reach them or you cant. Multimedia Keyboard A multimedia keyboard is designed to make it one-touch simple for the user to access often-used programs. There are special keys used to access the Internet, music, and other frequently used programs such as email. A typical multimedia keyboard contains buttons that control various computer processes, such as turning on the computers power, putting the CPU to sleep, and waking it up again.
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