Computers Science Engineering (Computer Component) - INPUT DEVICES (Functional Overview )

 

Computer Component - Functional Overview : 

1.1 THE INPUT UNIT

The input unit is responsible for accepting input i.e data and instructions from the user. This work is accomplished with the help of input devices.Device, in general,refers to an equipment.
The input unit is responsible for taking input and converting it into computer understandable form (the binary code). Examples of an input devices and media are : Keyboard mouse, Magnetic ink character reader (MICR), Optical mark reader (OMR), joystick etc.
Let us learn more about some most common input devices.

1.1.1 The Keyboard : 

The keyboard is a typewriter like device which is used to type in the letter ,digits, commands.A keyboard contains a matrix of switches (One switch per key). When pressed ,sends a digital code to the computer that determines which key has been pressed, sends a digital code to the when Caps lock is on, a code 010000001 is sent to computer : computer then translates this code to that you pressed 'A'.

(The Keyboard)

Advantages:

• Reliable way of inputting text and numbers.
• Available in variety of formats.

Disadvantage: 

• Not useful for entering some specific type of data (e.g picture , diagram, voice, video etc).
• Very slow while moving window or other objects.

1.1.2 The Mouse: The  mouse is pointing device  with a roller on its on its base.Mouse controls movement of pointer (also called mouse pointer on screen.When a mouse moves on  a flat surface , the cursor on the screen also moves in the button, and it may not have a wheel.

(The mouse)

Advantages:

• Ideal for pointing objects/options on desktop computers.
• Most familiar and easy to use pointing device.

Disadvantages:

• Need a flat space close to computer.

1.1.3 Joystick :

• Joystick are often used for playing computer games such as flight simulators. Mini- figure controlled joystick can be used to control a laptop cursor.  

(Joystick)

Advantages :

• Easy to learn to use,
• Not costly. 

Disadvantages :

• Moving is offered only in forward.

1.1.4 The Scanner :

A scanner is a device similar to a photocopier . A photocopier prints the given printed image/page on a paper.

Scanners come in a variety of sizes from hand-held models to desk top models as discussed below:

(i) Hand- held Scanners

(ii)  Flatbed Scanners

(iii) drum Scanners.

(scanner)

Advantages :

• Any image can be converted from paper into digital format and enhanced and used in other computer documents.

Disadvantages :

• Images can take up a lot of memory space.

1.1.5 Optical Character Reader (OCR):

An optical  character reader is used to read character of special type font printed on conventional ink.These days OCR are capable of reading hand written text also.

(OCR)

1.1.6 Magnetic ink character Reader (MICR) :

In this  method ,humans readable character are printed (such as cheques) using a special magnetic  ink. MICR mainly used in banks. Smart cards have magnetic strips that store information written in Magnetic Ink character format.

Advantages :

• Documents prepared for MICR are difficult to forge.

Disadvantage:

• MICR readers and encoders are expensive.

1.1.7 Bar Code Reader :

A bar code reader is also one of the most widely input devices. A bar code reader emits a beam of light which reflects off the bar code image. Once a bar code identified , the bar pattern is converted into the numeric code that can be processed later in any manner.

(Bar code reader)

1.1.8 Microphone :

We can send sound input to computers through a special input device called microphone or mic.A mic can work if your computer has a special hardware known as sound card.

(Microphone)

1.1.9 Digital Camera :

A Camera that stores images digitally rather than recording them on film is called digital camera.

(Digital Camera)

These are some major used input devices or examples of Input devices.

(Computer Science )