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What Is A Keyboard?

What Is A Keyboard

Date First Published: 4th July 2022

Topic: Computer Systems

Subtopic: Computer Hardware

Article Type: Computer Terms & Definitions

Difficulty: Easy

Difficulty Level: 1/10

Learn more about what a keyboard is in this article.

A keyboard is a basic input device made up of a panel of plastic keys that allows users to input letters, numbers, symbols, and perform other functions by pressing individual keys. Almost all keyboards have letters, numbers, symbols, arrow keys, control keys, function keys, and LED lights indicating num lock, scroll lock, and caps lock, but others may include extra keys, such as a number pad, keys to power down the computer or put it into sleep mode, keys to turn the volume up and down, light-up keys, and more. Common keyboard manufacturers are Microsoft, HP, and Logitech.

Windows and other operating systems allow users to alter the settings of a keyboard, such as the cursor blink rate, repeat rate, repeat delay, and more.

Uses Of Keyboards

Keyboards are used all the time to perform all sorts of tasks on a computer. These include:

  • Typing documents and inputting data into forms.
  • Entering commands in a command-line interface (CLI).
  • Controlling the volume of a computer.
  • Using function keys to perform specific tasks. The 'F' in F1 stands for function and it is used to show help.
  • Putting a computer into sleep mode or powering it off.
  • Screenshotting the computer screen and saving the screenshot to the clipboard.
  • Moving the text cursor on the screen using arrow keys.
  • Starting a computer in advanced troubleshooting modes.

Keyboard Layouts

Keyboards can be arranged in different ways and various keyboard layouts are available around the world. The most common layout is QWERTY, which is the first five letters of the keyboard layout. Other languages have different default keyboard layouts. For example, the default French keyboard layout is AZERTY.

The main reason why keyboards are not in alphabetical order dates back to manual typewriters. It is because the alphabetical order of keys created a typewriter jam due to typists typing so fast and two keys next to each other being pressed very quickly at the same time. The QWERTY design was created to slow typists down and the keys were arranged with the most common letters in hard-to-reach spots.

Keyboard Connections

Keyboards can connect to the motherboard using a wired connection, such as USB. PS/2 is used by older keyboards and consists of pins at the end of the connector. Wired keyboards use power from the computer rather than battery power.

As of now, a lot of keyboards connect to the computer wirelessly through Bluetooth and require batteries to work. Wireless keyboards require a receiver to be plugged into one of the USB ports of a computer and the receiver will then send a signal to the battery-powered keyboard. In order for keyboards to be used with the computer, they require a specific device driver. However, drivers for standard and non-advanced keyboards do not usually need to be downloaded as they are already included in the operating system.

Laptop and Mobile Device Keyboards

Due to their portable design, laptop keyboards are different to desktop computer keyboards. Instead of being separately attached to the computer, they are built into the hardware of the laptop. Laptop keyboards do not usually contain the number pad because of their limited size. However, an external keyboard can be connected to the laptop through USB. Laptops rarely have a PS/2 port for connecting an external keyboard.

Mobile devices do not have attached keyboards. Instead, they have on-screen keyboards that only display when a user is typing. However, some older mobile devices had built-in QWERTY keyboards below the screen. Mobile devices with physical keyboards on the screen are uncommon now. However, there are Bluetooth keyboards for mobile devices that can be connected to a mobile device.

Apple Keyboards

Apple keyboards are mostly identical to keyboards used on Windows desktop computers. However, some keys on Apple Keyboards are different. The differences between Apple and Windows keyboards are the three keys in the bottom left corner. The Windows key is replaced by the 'Alt option' key and the 'Alt' key is replaced by the 'Cmd' key.

Keyboard Shortcuts

For more information on keyboard shortcuts, see this article.

Keyboard shortcuts allow users to perform specific functions by key combinations, making it quicker to perform actions and reducing the period of time spent working with the mouse or touchpad. For example, 'Ctrl + C' is a shortcut for copying the selected text. Another example of a keyboard shortcut is the Windows key. Pressing this key displays the start menu.

Can A Computer Work Without A Keyboard?

Keyboards are considered peripheral devices as they are extra devices not part of the essential computer, such as the CPU. Without a keyboard, a computer can still run, but it would be impossible to type anything onto the computer. However, an on-screen can be used to enter text instead of a physical keyboard. It will display a virtual keyboard on the screen with all the keys. The mouse is used to click on the keys and this method is time-consuming.

Can Keys Be Remapped?

It is definitely possible to remap one key to another or disable certain keys. This is useful if one key is missing. For example, if the 'K' key is missing, the 'F1' key could be remapped to the 'K' function, changing the function of the key. Microsoft Keyboard Layout Creator, a downloadable program developed by Microsoft, allows users to modify keyboard layouts. It is compatible with Windows. Sometimes, keys can be remapped by a virus infection, causing the position of keys to be reconfigured or the keyboard language to be altered without the user's permission.

How Does A Keyboard Work?

Keyboards are like smaller versions of a computer. Underneath the keys is a grid of circuits. Each time a key is pressed, it presses a switch, completing the circuit and enabling a small amount of current to flow through. If a key is pressed and held, the processor will assume that is being pressed over and over again. Keyboards have their own processors and circuitry that carries information to and from that processor.

The location of a closed circuit on the grid of keys is compared to the character map in the ROM of the processor when it discovers a closed circuit. A character map is a lookup table or comparison chart that informs the processor of the location of each key within the grid and what each keystroke means. For example, the character map informs the processor that whilst pressing the 'a' key itself produces a lowercase 'a' pressing the 'a' key along with Shift produces a capital 'A'.

Switches with rubber domes are widely used. They use small, flexible rubber domes that each have a solid carbon centre. A plunger on the bottom of the key presses on the dome whilst the carbon centre presses against a flat, hard surface below the key grid when a key is pressed.

The carbon centre completes the circuit as long as the key is held. The rubber dome springs back to its normal form when the key is released, pushing the key back up to its resting position. Because of the rubber layer covering the key grid, rubber dome switch keyboards are priced, have a strong response, and are quite durable to spills and damage.

History

Even though typewriters are the predecessor of all key-based text entry devices, keyboards come from teleprinters and keypunches. This was how modern keyboards got their layouts. Devices similar to teleprinters were used to both type and transmit stock market text data from the keyboard across telegraph lines to stock ticker machines to be copied and displayed onto ticker tape as early as the 1870s.

Herman Hollerith developed the first keypunch devices that quickly evolved to include keys for text and number entry in a similar way to normal typewriters by the 1930s. It is evident that the development of the earliest computers used electronic typewriter keyboards as the development of the ENIAC computer used a keypunch device as both the input and paper-based output device, whilst the BINAC computer also used an electromechanically controlled typewriter for both data entry onto magnetic tape and data output.

The keyboard was the primary computer peripheral device in the generation of personal computing until the introduction of the computer mouse in 1984. By this point, screen icons were relatively strong in graphics, replacing text-only user interfaces with minimal graphics.