User:Shahir21/Input Devices

What is Input?

Input refers to the instructions that are fed into the computer. There are different types of input. These include:

•Data is the raw facts and figures.

•Programmes are a group of instructions that a computer follows.

•Commands are special words that are fed to the computer to perform a task; like RUN “MSWORD.”

•User Answer is the users answer to the computers question; like YES, NO, or CANCEL.

Input is a very important step. Without it, you would not be able to produce output. Even the most basic steps involve input. Some of the basic steps the computer performs are:

Input Devices

Input devices are used by people to communicate with computers. It is necessary for input devices to data into binary form so that the computer may understand it. Major input devices include:

•Keyboard

•Mouse

•Trackball

•Joystick

•Scanner

•Microphone

•Camera

•Speech Recognizer

•Bar Code Reader

•Touch Screen

Keyboard

The keyboard is the most commonly used input device. Keyboards have different sizes and shapes. They depend on the type of the computer that is being used. The closest things that you would find to keyboards are typewriters. The keyboard is often referred to as the main input device. Te keyboard has all the letters of the alphabets, numbers 0-9 and other special operating keys (CTRL, ALT, SHIFT, TAB, INS, DEL, HOME, END, and ESC).

Mouse

A mouse is an input device that controls the cursor on the monitor. It has two and sometimes three buttons and a long cable connecting the mouse with the computer. The mouse is the easiest input device to operate. All the user needs to do is simply move the mouse on some smooth surface, guiding the cursor to the desired location on the monitor and click either three of the buttons.

Trackball

A new and improved version of the mouse is a trackball. Instead of moving the whole object around, all the user needs to do is move the ball on top of the device. Trackballs are also present on some models of wireless keyboards and act as mouse.

Joystick

Joysticks are most commonly used for playing games on the computer. It is similar to a mouse and trackball. The only difference between a mouse and a joystick is that the cursor stops moving when the mouse stops moving, but in a joystick the cursor continues to move until the joystick itself is set into an upright position. Now new game controllers like for the PlayStation®, have joysticks on them known as analog stick.

Scanner

A scanner is an input device that basically looks like a photocopier. It basically scans any document kept on its glass bed and then sends the contents of the documents to the computer. The page(s) is/are scanned in the form of images and can be edited or resized by suitable software that usually comes with the scanner.

Microphone

Microphone is an input device that is used to transfer sounds into the computer through a sound recording or voice recognizing software. It can be connected to the computer via cable.

Voice Recognizer

Voice or Speech Recognition is the ability of a machine or programme to take and understand dictation, or interpret and carry out verbal and spoken commands. It is the most convenient way of entering data into the computer. Some programmes like Microsoft Word 2007® or Apple® devices offer voice recognition services.

Digital Camera

A camera is not what you would call a proper input device although it can take pictures without a conventional film which are stored in a memory card or its built-in memory which can be later transferred to a computer via USB (Universal Serial Bus) Cable for viewing or printing. Bar Code Reader Bar codes or UPCs (Universal Product Codes) are black and white lines that are printed on books and certain goods. They represent numbers which give a detailed description of the object e.g. its weight, name, price, etc. Bar codes can usually be found in markets, libraries and other good purchasing shops. These lines can be scanned via a bar code reader.

Touch Screen

A touch screen is a unique device. It is an input device as well as an output device. Some of the screens are sensitive to pressure while some have thermal pads which sense the body heat. A user interacts with the computer by touching picture and text displayed on the screen.

References

This document has not been taken from any website. Only texts from Aitchison College Computer Studies Book E1 have been taken and edited in some places