Computer Hardware refers to the Physical components of a computer that can be seen and touched by the user. By the use of these hardware device, it made very easy for the computer for processingits data, store and retrive. Hardware is one of the basic and necessary parts of a computer system.
Input Devices
An input device can be defined as an electro mechanical device that allows the user to feed data into the computer for analysis and storage and to give commands to the computer. The data is entered into the main memory through the input devices.
The accept instructions from the user and convert the accepted instructions into the machine language.
Keyboard
It is one of the most common input device. The user can type text and command using this device. The layout of the keyboard was borrowed from the regular typewriter with some additional keys. Keyboard is used to enter data or information in a computer system, which may be in numeric form or alphabetic form. When key is pressed, keyboard interacts with a keyboard controller and keyboard buffer.
There are different types of keyboard such as QWERTY, DVORAK and AZERTY.
QWERTY keyboard contains 104 keys.
Pointing Devices
A Pointing device is used to communicate with the computer by pointing to the locations on the monitor. Movments of the pointing device are echoed on the screen by movements of the pointer.
Mouse
It is a small handheld device having two buttons on its upper side and also has a small wheel between these buttons. It is a pointing device which provides a mean to input data and commands in graphic form by selecting through moving an arrow called pointer on monitor.
Mouse was invented by douglas Engelbart at standford research center in 1963.
There are some input device:
Joystic, light pen, touch screen,
Barcode Reader, Optical Mark Reader, Optical character recognition ,
Megnetic ink character Recognition, Smart card reader,
Biometric Sensor, Scanner, Microphone, Webcam, PC card etc.
Output Devices
An output device is any piece of computer hardware equipment used to communicate the results of data processing carried out by an information processing carried out by an information processing to the outside world.
Some of the commonly used output devices are Moniter, Printers, Plotter, Speaker, Headphones, Projector etc.
Both Iput-nOutput Devices
Few devices that give input and also show or get the output through same device. These are as follows,
1. Modems
2. Network cards
3. Touch screen
4. Headsets
5. Facsimile(FAX)
6. Audio cards / Sound cards
Input/Output Port
The peripheral devices can be connected to computer in several ways. Input/Output ports are the external interfaces that are used to connect input and output devices like printer, moniter and joystick to computer.
The I/O devices are connected to the computer via the serial and parallel ports, Universal Serial Bus, Firewire ports, etc.
