What is the Keyboard?

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A keyboard is a device used for input, enabling the typing of letters, numbers, and symbols into a computer or electronic device. It typically features a set of keys organized in a particular layout, like QWERTY or DVORAK.

A computer keyboard is an input device, either built-in or peripheral, modeled after the typewriter keyboard, using an arrangement of buttons or keys that act as electronic switches or mechanical levers. Teleprinter-style keyboards, which replaced punched cards and paper tape technology, have been the main method of input for computers since the 1970s, while the computer mouse has been supplementing since the 1980s, and touchscreens since the 2000s.

Keyboard Functionality

Typically, keyboard buttons have engraved or printed characters, where each press corresponds to a written symbol. However, some symbols require holding or pressing several keys in sequence or simultaneously. While most keys produce characters like letters, numbers, or symbols, others, such as the escape key, trigger system commands. In modern computers, software typically interprets the keypresses, and the scan code sent to the computer identifies which physical key was pressed or released.

Keyboards are usually used for entering text, numbers, and symbols into software applications like word processors, web browsers, or social media apps, while virtual keyboards are used with touchscreens.

Evolution of Keyboards

The following is the evolution of keywords −

• 1870s − Devices similar to teleprinters transmitted stock market data from the keyboard via telegraph lines to stock ticker machines, copying it onto ticker tape.
• 1907-1910 − The teleprinter's more contemporary form emerged, developed by American mechanical engineer Charles Krum and his son Howard, with early input from electrical engineer Frank Pearne.
• 1930s − Keypunch devices evolved to include keys for text and number entry similar to those of typewriters. Herman Hollerith invented earlier keypunch devices.
• Mid-20th Century − The teleprinter keyboard was used for communication, while the keypunch keyboard was used for data entry and storage. The ENIAC computer incorporated a keypunch device for input and paper-based output, while the BINAC computer used an electromechanical typewriter for entering data onto magnetic tape and output.
• 1984 − The mouse was introduced as a consumer device. However, the keyboard remained the most integrated peripheral for personal computers, even with the rise of graphics-rich interfaces.
• Present − Keyboards continue to be central to human-computer interaction, although virtual keyboards are more common with mobile personal computing devices like smartphones and tablets.

Types of keyboards

Different types of keyboards cater to specific needs, with the most common full-size layouts referred to as ISO (ISO/IEC 9995-2), ANSI (ANSI-INCITS 154-1988), and JIS (JIS X 6002-1980). ANSI standard keyboards, for instance, have keys on three-quarter-inch centers and a key travel of at least 0.15 inches.

Full-size keyboards generally have 101, 104, or 105 keys, depending on the standard, with modern US keyboards typically containing 104 keys and others globally containing 105. However, some compact designs skip certain keys or sections to save space, such as the Numpad, with designs referred to as "tenkeyless" or TKL.

Desktop and Laptop Keyboards

Desktop keyboards often include a numeric keypad, alphabetic characters, numerals, punctuation marks, special characters, diacritics, and function keys. They resemble electric typewriter keyboards but with additional keys like the command or Windows keys.

Laptop keyboards typically have shorter keystroke distances and reduced key sets, and may not include a numeric keypad. They usually use scissor switches instead of rubber domes, a trend opposite to full-size keyboards.

Flexible Keyboards

Flexible keyboards combine normal and laptop-style keyboards, offering a full key arrangement with a shorter key distance and flexibility for storage. Most flexible keyboards are made of silicone, making them water- and dust-proof, which is beneficial in environments like hospitals.

Handheld Ergonomic Keyboards

Handheld ergonomic keyboards are designed to be held like a game controller and often contain all alphanumeric keys and symbols but require pressing two keys at once to access them. They allow for mobility while typing and may include a trackball mouse.

Thumb and Numeric Keyboards

Thumb keyboards, used on devices like PDAs and smartphones, are smaller external keyboards useful for limited workspaces. Numeric keyboards, or numeric pads, include numbers, mathematical symbols, and function keys and are often used on laptops without a numeric keypad.

Multifunctional Keyboards

Multifunctional keyboards offer extra functions beyond standard keyboards, controlling multiple PCs or workstations and offering customized keypads, programmable function keys, or touchscreens to control media, alarms, and more. These keyboards are common in high-performance environments like trading or control rooms.

Keyboard Commands

The following are some of the keyboard commands using the Control key (or Command key on Macs) −

• Ctrl+A − Selects all data within a given view
• Ctrl+B − Changes the selected text to bold font
• Ctrl+C − Copies selection
• Ctrl+D − Bookmarks the current page in most browsers
• Ctrl+F − Opens a search box for the current browser or application window
• Ctrl+I − Changes the selected text to an italicized font
• Ctrl+P − Opens a print dialogue box for the current window
• Ctrl+V − Pastes the copied selection
• Ctrl+X − Cuts selection
• Ctrl+Z − Undoes the most recent action