Input Devices


An input device is any device that provides input to a computer. There are dozens of possible input devices, but the two most common ones are a keyboard and mouse. Every key you press on the keyboard and every movement or click you make with the mouse sends a specific input signal to the computer. These commands allow you to open programs, type messages, drag objects, and perform many other functions on your computer.
Since the job of a computer is primarily to process input, computers are pretty useless without input devices. Just imagine how much fun you would have using your computer without a keyboard or mouse. Not very much. Therefore, input devices are a vital part of every computer system.

Manual Input Devices

A type of control device that requires an individual to manually press a button or turn a switch. Push buttons and selector switches are types of manual inputs. Input devices allow us to enter data into a computer. The computer processes the data and then produces outputs that we can understand using an output device, but any way input devices can be manual or automatic. The processing is mainly handled by the Central Processing Unit (CPU).
The most common manual input devices are the keyboard and the mouse.

Concept Keyboardconcept keyboar.jpg

Each button on a concept keyboard relates to a particular item or function. Buttons can be labelled with text or a picture. Fast food restaurants often use concept keyboards because very little training is needed to operate them and they're efficient, which means that a single button can order an entire meal. To give a clearer idea we have presented some examples.

Joystick images.jpg

Joysticks used to be popular with games but have slowly been replaced by other types of game controller. In construction, joysticks are used to control machinery such as cranes.

Digital Camera digital camara.jpg
A digital camera takes pictures and can usually record video too. The pictures it takes and the videos it records are stored in files. These files can be copied to a computer and later edited.

Automatic input devices
A type of control device that is set to automatically control each step in a process. Pressure switches, flow switches, and temperature switches are types of automatic inputs.
Sensors are often used as part of a feedback cycle. They collect data continuously and are typically linked to a control program that specifies acceptable levels, for example, the minimum and maximum temperature in a green gouse. The control program decides what to do next based on the data it's fed by the sensors.

Barcode reader
Barcodes are represented by black vertical bars and are read by a barcode reader. Barcodes are printed on nearly every product you buy, each product has a unique code. When read, information stored in the shop's database is recalled, such as the product name and price. This information later appears on your receipt. The scanning process also assists in stock management, reducing the stock by one each time a product is scanned/sold.

Magnetic strip (or stripe) reader
Debit card
Debit card

Magnetic stripes are built into many plastic cards such as debit or credit cards and personal identity cards. The magnetic strip on the back of the card can hold the personal details of the card owner and, with the necessary PIN, will allow access to secure information, for example bank account details. Data stored on the strip is scanned and input into a computer system by a magnetic stripe reader.

Magnetic Ink Character Reader (MICR)
Magnetic ink characters appear at the bottom of checks. Banks use MICR to read the numbers from the bottom of checks to obtain data such as account numbers and bank sort codes. A particular font is used that makes it easy for the machine to discriminate between characters. The ink is magnetic, this makes it immune

to creases and dirty marks.

Optical Mark Reader (OMR)
An OMR reads marks made by pencil on a printed form into the computer. OMR systems are suited to read pre-printed forms and check boxes such as National Lottery number selection sheets and multiple choice exam papers.