Input Device
Input Device || Input Hardware || Computer Hardware || Types of Computer Hardware:Input Device:
Can computer work without any instruction?
A
computer needs instruction to perform any task. So, we need to give instruction
to computer in order to perform task. Instruction can be given using hardware
i.e. input devices. It is not possible to operate computer without input
device. The input devices are used to enter data and instructions into the
computer for processing.
The
devices such as keyboard, mouse, joystick, scanner, microphone, digital camera,
webcam, light pen, etc. are known as input devices or input hardware. At
present different types of input devices are used in computer for entering data
or giving instructions. Some of the commonly used input devices are described
below:
1. Keyboard: Keyboard is the basic and fundamental input device
of a computer. We can give input to the computer through keyboard. The Input
may be data such as letters, numbers, symbols and instruction. There are
different types of keys on the keyboard. The keys on the keyboard are grouped
into five different groups. They are :
i)
Alphabet Keys (a
– z)
ii)
Numeric Keys (0
– 9)
iii)
Functions Keys (F1
– F12)
iv)
Cursor Movement Keys
v)
Special Purpose Keys
The standard keyboards used in PC have 104 keys and
the multimedia keyboards have more than 104 keys. The laptop computers have
fewer keys. The different keys perform different functions. The layout of a
keyboard differs with brands and manufacturing companies. The most common
English Language key layout is the ‘QWERTY’ layout.
2. Mouse: The mouse is another commonly used input device with
GUI programs in the personal computer (PC). It is handheld input device that
looks like a mouse It helps user to input data/instructions into the computer
which are seen on the window, means used to point objects and give command to
the computer. We can move objects, open them, change them, and perform other
actions using mouse. It is also called a pointing input device
because it points any items seen in the monitor.
When we move the mouse on the mouse pad, the mouse pointer (cursor) on the screen moves in the corresponding direction. You can point objects moving mouse pointer (cursor) and select them by clicking or double clicking over them. It can be used for drawing lines, curves and different shapes.
Generally, a mouse contains two buttons: a left button that is called the primary button and right button that is called secondary button. The primary button is the one you will use most often. Different buttons have different functions depending on the running program. The newly developing mouse also includes a scroll wheel between the buttons.
Joystick:
Joystick is an input device. It is also a primary input device like mouse that is used to point and move objects on the screen. It is specially used for playing computer games. It is like a stick having one or more push buttons. We can compare it with gear leaver of motorcar.
Trackball
Trackball is similar pointing device like mouse which consist a movable ball in a socket. You can roll the ball with your fingers or palm to move the pointer on the screen. As you move the ball, the pointer moves on the screen in the same direction. It is mostly used on portable computers such as laptop, palmtop, notebook, etc. for pointing and choosing GUI icons.
Touch Screen:
Touch screen is a kind of video display screen that consist of touch sensitive display panel covering the screen. It is a screen with touch sensitive points or program Icons which you can use with your finger or a stylus. A stylus is a pen shaped pointing tool. You can use your fingers to select objects on the screen and give commands to the computer like a mouse.
Touch Pad:
A touch pad is a small, touch-sensitive pad used as an input device commonly in laptop computers. By moving a finger along the pad, you can move the pointer on the screen. The touch pad contains two buttons which work as a computer mouse standard buttons.
Scanner:
A scanner is an input device that optically scans (copies) images, printed texts, handwritings, or an object, and sends them to the computer. The scanner converts the images, printed texts, handwriting, or an object into digital form (binary format) and sends to the computer for processing. The scanner can perform such task which cannot be done by keyboard and even mouse. So it is also called as indirect input device.
Web Camera:
This is one of the latest inventions of computer hardware that takes photos or videos and sends into the computer. It is widely used in Internet Chatting and for video conferencing. It is specially used in messenger programs such as Yahoo! Messenger, Windows Live Messenger and Skype.
Microphone:
A micro phone is an input device that is used to input voice or sound into the computer. We can record speech, songs, etc. in the computer using microphone. A computer stores recorded voice and sound in the digital format so that they can be processed as required.
When we move the mouse on the mouse pad, the mouse pointer (cursor) on the screen moves in the corresponding direction. You can point objects moving mouse pointer (cursor) and select them by clicking or double clicking over them. It can be used for drawing lines, curves and different shapes.
Generally, a mouse contains two buttons: a left button that is called the primary button and right button that is called secondary button. The primary button is the one you will use most often. Different buttons have different functions depending on the running program. The newly developing mouse also includes a scroll wheel between the buttons.
Joystick:
Joystick is an input device. It is also a primary input device like mouse that is used to point and move objects on the screen. It is specially used for playing computer games. It is like a stick having one or more push buttons. We can compare it with gear leaver of motorcar.
Trackball
Trackball is similar pointing device like mouse which consist a movable ball in a socket. You can roll the ball with your fingers or palm to move the pointer on the screen. As you move the ball, the pointer moves on the screen in the same direction. It is mostly used on portable computers such as laptop, palmtop, notebook, etc. for pointing and choosing GUI icons.
Touch Screen:
Touch screen is a kind of video display screen that consist of touch sensitive display panel covering the screen. It is a screen with touch sensitive points or program Icons which you can use with your finger or a stylus. A stylus is a pen shaped pointing tool. You can use your fingers to select objects on the screen and give commands to the computer like a mouse.
Touch Pad:
A touch pad is a small, touch-sensitive pad used as an input device commonly in laptop computers. By moving a finger along the pad, you can move the pointer on the screen. The touch pad contains two buttons which work as a computer mouse standard buttons.
Scanner:
A scanner is an input device that optically scans (copies) images, printed texts, handwritings, or an object, and sends them to the computer. The scanner converts the images, printed texts, handwriting, or an object into digital form (binary format) and sends to the computer for processing. The scanner can perform such task which cannot be done by keyboard and even mouse. So it is also called as indirect input device.
Web Camera:
This is one of the latest inventions of computer hardware that takes photos or videos and sends into the computer. It is widely used in Internet Chatting and for video conferencing. It is specially used in messenger programs such as Yahoo! Messenger, Windows Live Messenger and Skype.
Microphone:
A micro phone is an input device that is used to input voice or sound into the computer. We can record speech, songs, etc. in the computer using microphone. A computer stores recorded voice and sound in the digital format so that they can be processed as required.