INPUT DEVICES

By ADEFILOLA K.O

WHAT ARE INPUT DEVICES?

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They are hardware devices that allow data to be input into the computer system. This can be done manually (using Manual Input Devices) or automatically (using Automatic Input Devices).

Manual Input Devices:

KeyboardMouseTouchpadJoystickScannerTouchscreenDigital CameraMicrophoneGraphics Tablet

Automatic Input Devices:

M.I.C.RO.M.RO.C.RBarcode ReaderMagnetic Stripe CardSensors

The ideal input devices that is used to input texts, numbers and instructions (eg CTRL+V) into the computerMost keyboards have QWERTY layout.

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Keyboards

There are different types of keyboards1.Ergonomic keyboards:- Designed to

reduce health related problems like RSI.

2.Concept keyboards:- Uses icons or phrases instead of standard letters.

Advantages:

1.Fast entry of texts into documents.

2.A well known method of data entry.

3.Most people find it easy to use.

4.Easy to do verification test.

Disadvantages:

1.People with limited arm/wrist may not find it easy to use.

2.Data entry may be slow.

3.They use up valuable desk space.

MICEPointing devices that are used to control the position of a pointer on the screen, selecting commands, resizing images as well as opening, closing and minimising applications.

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Advantages:

1.Faster to select options.

2.Rapid navigation through applications.

3.Take up little desk space.

Disadvantages:

1.People with restricted hand/wrist movement may not find it easy to use.

2.They get damaged easily.

3.They are difficult to use where there is no flat surface.

Mice

JOYSTICKSUsed in playing computer games and simulations to mimic actual controls.

Advantages:

1.A mouse is better and easier in controlling on-screen pointers

Advantages:

1.Easier to navigate round a screen more than a mouse

2.Control is in three dimensions.

TOUCH SCREENSAllows a user to simply touch the touch the button/icon on the screen to select a text, task or action. It is mostly used on phones, ipads, petrol stations, ATMs, Interactive boards and other payment methods.

Advantages:

1.Fast entry of options than keyboards.

2.Very easy to choose options.

3.User friendly method of inputting options4..5.They are tamper proof.

Advantages:

1.Limited number of options are available.

2.Can lead to RSI.

3.Screen can get damage or dirty.

Magnetic Stripe ReadersUsed to read information on the magnetic stripe found on the back of credit cards, debit cards, security card, etc.

Advantages:

1.Data entry is faster.

2.Data entered are error free.

3.Information held on magnetic stripe is secured.4.It can not be damaged by oil, water or moisture.

5.They are no moving parts, so the are physically robust.

Disadvantages:

1.Data are lost when card is damaged.

2.Card readers do not work in a distance.

3.Information are not readable by card users.

Chip and PIN ReadersUsed where payment are made using cards (e.g. hotels, restaurants, supermarkets, travel agencies.

Disadvantages:

1.Someone else may read the PIN while a user is typing in his PIN.

Advantages:

1.Provides more secure payment system than magnetic stripe.

2.Chip does not need to be in contact with the reader.

ScannersUsed to scan documents and pictures and convert them into a format for use in various application software.

Advantages:

1.Images can be scanned and edited.

2.They are faster and more accurate in data entry.

3.It makes it possible to recover damaged images and documents

Disadvantages:

1.Quality can be limited, depending on how good the scanner resolution is.

Barcode ReaderUsed in supermarkets, shops, libraries and other companies to read information in the form of barcodes marks on product casings.

Disadvantages:

1.It is relatively expensive to setup.

2.It is relatively expensive to manage.

3.Works with computers or POS terminals

Advantages:

1.Faster in data entry.

2.Less data entry error.

3.Enables automatic stock control.

4.When the price of an item changes, only the central database needs to be updated

Optical Mark RecognitionReads marks written in pen and pencils. OMR devices are used to read questionnaires, multiple choice examination papers and many other types of forms where responses are registered in the form of lines or shaded areas.

Disadvantages:

1.Input data may not be accurate if forms are not carefully handled or shaded.2.There may be need for manual check if forms are not properly filled and this may lead to a waste of time

Advantages:

1.Very fast way of inputting the results of a survey/research.

2.It is more accurate than keyboards and OMR.

3.Reduce cost of inputting.

4.Very useful where results of tests are needed very fast.

Optical Character RecognitionTakes scanned text and converts it into a computer readable form. The text can then be used in various application packages.

Disadvantages:

1.It usually have difficulties reading handwritings.

2.It is not a very accurate technique.

Advantages:

1.It is a more faster data entry system than manually keying in data.

2.Number of errors is reduced.Reduce cost of inputtingResults of tests are needed very fast

Magnetic Ink Character RecognitionReads characters printed in a special ink (containing iron particles). MICR is primarily used to process cheques in banking operations.

Disadvantages:

1.Only certain characters can be read.

2.It is a more expensive method of data entry.

Advantages:

1.It offers greater security than OCR since the printed characters cannot be altered.

2.There is no manual input, thus errors are reduced.

3.Characters can still be read even when somebody write on them.

Digital CamerasUsed to produce photographs for transfer to a computer directly or to print out by connecting directly to a printer. Photographs can also be uploaded directly into applications software such as word processors, DTP, etc.

Disadvantages:

1.User needs to be computer literate.

2.There is some artistry lost since some clever software can make corrections to photographs.

3.Quality of photograph depends on quality of camera lens.

4.Images can easily fill up computer memory.

Advantages:

1.It produces better quality photographs.

2.Easier and faster to upload photographs to a computer.

3.No need to develop photographs before printing.

4.It is easy to delete unwanted images.

5.Memory card used can store several photographs.

Web Cameras (WEBCAMS)Used in video conferencing. That is, chatting online and at the same time displaying the images of the people in the conversation.

Disadvantages:

1.Pictures are often of poorer quality.

2.Some webcam need to be connected to the computer before use.

Advantages:

1.Can be left on constantly on the computer rather than using a digital camera.

2.Allows images of someone faraway to be viewed while chatting.

MicrophonesUsed to input speech/ sounds to be used in various applications and also in voice recognition software.

Disadvantages:

1.Sound files can use up a lot of computer memory.

2.Voice recognition software is not as accurate as typing manually. For instance, it may not be able to distinguish the difference between ‘there’ and ‘their’.

Advantages:

1.It is faster to read-in text than to type it in using a keyboard.

2.Sound can be manipulated in real time rather than a recording done at earlier stage.3.It can improve safety and security when used in voice activation systems. E.g. switching on a radio while driving.

Graphic TabletLike an electronic tracing paper used for graphic designing.

Disadvantages:Advantages:

1.It