Peripherals. Input devices.

What are peripherals? Peripherals are physical units attached to the computer. They include:

Input devices, which let us enter data and commands (e.g. the keyboard and the mouse)

Output device, which let us extract the results (e.g. the monitor and the printer)

Storage devices, which are used to store information permanently (e.g. hard disks and DVD-RW drives).

Peripheral equipment is always separated from the central processing unit (CPU) by a device controller.

Peripherals normally have no function when not connected to a computer. They connect over a wide array of interfaces. The most common peripheral linking device is probably USB technology. Some peripherals are even used for security. A good example of this is the dongle. The dongle * is often used to protect very expensive applications from software piracy.

The mouse and the keyboard are the most common input devices. The keyboard is an input device which we use to enter data. It translates numbers, letters, symbols and control keys into signals that can be interpreted by the PC. The keyboard helps us tell the computer what we want it to do. QWERTY is the most common modern-day keyboard layout on English-language computer and typewriter keyboards. It takes its name from the first six letters seen in the keyboard's top first row of letters.

The computer mouse is a device which helps us navigate through different programs.

It helps us give the computer commands which the keyboard cannot. Or commands which would otherwise take a longer time to give on the keyboard. The mouse makes a lot of things simpler.

We can also interact with a computer by using one of these: a touchpad, touch screen, a light pen, a scanner, a microphone and etc.

Touch pads are most commonly built into a laptop computer. A touch pad is a rectangular plastic piece which can control the pointer on a computer simply by dragging your finger across its surface. Touchpads were originally known as trackpads.

A scanner is a device that uses light to read an image or text and turn it into a digital message.

Some peripherals, such as touchscreens, work for both input and output. A touchscreen is a display screen that is sensitive to the touch of a finger or stylus. By using the touch of a finger on a computer screen, the computer is able to receive input from the movement of your finger to control operations of the computer. The finger transfers electrical currents to the computer.

Without any input devices, a computer would only be a display device and not allow users to interact with it, much like a TV.

*dongle – Защитная заглушка, электронный защитный ключ (аппаратное средство защиты программного обеспечения и данных от несанкционированного доступа)