Chapter 2- Input and Output Devices

Front

Input Devices and Their Uses

Back

• An input device is any hardware device that allows a user to enter data or instructions into a computer directly.

• An input device can send data to another device, but it cannot receive data from another device.

• Input devices are necessary for a computer to receive commands from its users and data to process; they are under the user's control or can be direct data entry.

Front

Keyboards Uses:

Back

Uses:

• Input of data into applications software

• Typing in commands to the computer

Front

Keyboards Advantages:

Back

• Fast entry of new text into a document.

• Well-known method.

• Easy to use for most people.

• Easier to do verification checks as data is entered (can immediately compare the source document with typed data on the screen).

Front

Keyboards Disadvantages:

Back

• It can be difficult to use if the user has limited arm/wrist use.

• Slow method when compared to direct data entry.

• It is a fairly large device that uses up valuable desk spa.

Front

Numeric keypads

Uses:

Back

• Automatic teller machines (ATMs), where the customer can key in their PIN, amount of money, etc.

• Mobile phones allow phone numbers, etc., to be keyed in.

• Point of sale terminals (POS) in case the barcode reader fails to read the barcode – the number has to be keyed in manually by the operator.

• Chip and PIN devices when paying by credit/debit cards.

• Fast entry of numeric data into a spreadsheet.

Front

Numeric keypads

Advantages ;

Back

• Faster than standard keyboards when entering numeric data.

• Because many are small devices, they are very easy to carry around.

Front

Numeric key disadvantages ;

Back

• Sometimes, they have small keys, which can make input more difficult.

• Sometimes, the order of the numbers on the keypad is not intuitive.

Front

Mouse:

Uses:

Back

• Opening, closing and minimizing software

• Grouping, moving and deleting files.

• Image editing, for example, controls the size and position of a drawing pasted into a document.

• Controlling the position of a pointer on the screen to allow selection.

Front

Mouse:

Advantages:

Back

• It is a faster method for choosing an option than a keyboard.

• It's a very quick way of navigating through applications and the internet.

• Does not need a large desk area when compared to a keyboard.

Front

Mouse Disadvantages:

Back

• It can be more difficult for people with restricted hand/wrist movement than using a keyboard for data entry.

• Easy to damage, the older type of mouse quickly becomes clogged up with dirt.

• Difficult to use if no flat surface is readily available.