The keyboard is the most common and widely used input device.Using a keyboard for too long can lead to health problems such as repetitive strain injury (RSI).To try to overcome this, different styles of keyboard have been developed, for example, the ergonomic keyboard. They are supposed to put your hands into a much more natural position than a traditional keyboard.
The advantages of keyboard are:
1. Keyboards have special key that preform specific functions. 2. Instead of using the mouse to move the cursor you can use the arrow key situated on the keyboard to move the cursor on the monitor. 3. Keyboardare less expensive because it comes with every computer. 4.People are used to using keyboards to enter data, they need very little training 5.Specialist keyboards are available e.g. ergonomic, gaming keyboards
The disadvantages of keyboard are:
1. The person using the keyboard have to learn how to type. 2. The frequent movement from keyboard to move and back could cause carpal tunnel syndrome. 3.Excessive use can lead to health problems such as repetitive strain injury (R.S.I.) 4. Keyboards are not suitable for creating diagrams.
5. If you can't touch type, it can be time consuming to enter data.
The Computer Mouse is considered an input device. With a click of a button , the mouse sends information to the computer , the computer mouse is an interesting device that offers an alternative way to interact with the computer beside a keyboard. Atypical Mouse has two buttons. At the top of the device you will a left and right button which allows for “click”. There is scrolling wheel between two buttons.
The advantages of Mouse are:
1. A mouse is better for fine movements and adjustments than most of the alternatives. 2. Very maneuverable, can access any part of the screen in an intuitive way rather than using arrow keys. 3. They are the easiest way to use a computer (in a way that a keyboard never could). 4.A mouse is faster and easier to use than the keyboard. It has a greater range of motions than the arrow keys. 5. Can be installed without any installation software.
The disadvantages of mouse are:
1. An external mouse requires space, making it nearly impossible to use on an airplane. 2. A mechanical mouse needs to be cleaned regularly or it will get clogged with lint and dust. 3. The cord on most mice can get hung up and drag, making the mouse difficult to use. 4. Can contribute towards carpal tunnel syndrome and repetitive strain injury. 5. Difficult to use if you're disabled or have arthritis - but can be re-designed. Barcode Reader:-
A bar code is made up vertical lines (bars) and spaces. The sequence of bars and spaces of different thickness represents a sequence of numbers. A bar code reader uses a laser beam to read the code. The laser beam moves over the barcode and is reflected by the lighter bars and absorbed by the darker bars.
The advantages of Barcode Reader are:
1. You need both the chip and the PIN to make successful transactions in store. 2. Putting magnetic stripes on the cards are not expensive, so the cards are cheap. 3. Bar code readers eliminate the need for manual entry of data. 4. It is proven to be very efficient in inventory, point of sale and tracking. 5.They can be read even when they are on curved surfaces or upside down and the check digit that is included in the code makes it reasonably good at rejecting errors.
The disadvantages of Barcode Reader are:
1. Input is limited to a number code.
2. An extra layer of packaging is needed for multi-pack goods because they need a different barcode to the one on the individual items. 3. Magnetic stripes may get damaged or the stripe reader could break down. 4. Not accurate, because it first compares to a list then the one closest is chosen. 5.System Failure may cost more delays.