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An input device is a hardware device that sends data to the computer. It transforms information in the external world for consumption by a computer.
Examples : Keyboard, Mouse (pointing device), Barcode reader, Digital camera, Gamepad, Joystick, Microphone, MICR (Magnetic Ink Character Recognizer), Remote, Scanner, Webcam, OMR (Optical Mark Reader), OCR (Optical Character Recognizer)
Key board: Key board is the primary text input device for the computer. It was very popular when DOS was the popular operating system. After the emergence of Windows, its role became limited to dealing with text and for some commands only. The keyboard contains certain standard function keys, such as the escape key, tab, cursor, movement keys, and shift control keys. Macintosh keyboards connect to the Apple Desktop Bus (ADB), which manages all forms of user input- from digitizing tablets to mice.
Pointing devices
A pointing device is a human interface device that allows a user to input spatial data to a computer . The mouse is an integral part of any personal computer. It is a small device that can be moved across a pad in order to point to a place on a display screen and thus execute a command by clicking it. Though it is a primary input device, it is not suitable for dealing with text. A cable connects the mouse to the computer. Multimedia developers who are engaged in image or video editing may wish to use more sophisticated pointing devices like a tracker ball or tablet which gives developers finer control over the position of the pointer without moving their hands.
Microphone is another input device that can interpret dictation and also enable us to input sound. Sound cards convert sound from digital to analogue for output to speakers.
Digital camera records and stores photographic images in digital form that can be fed to a computer as the impressions are recorded or stored in the camera for later. Once a piece of video has been recorded it needs to be captured; digital video cameras can be connected directly to one of the USB or serial ports on the desktop computer but analogue video needs to be captured via a video capture card. Video capture cards receive analogue video signals through one of their ports and sample it at a frequency up to 30 frames per second, a resolution of 768 by 576 pixels and a sample size of 24 bits per pixel. Video capture requires high specification desktop computers with a fast, high capacity hard disk drive to cope with the input video data. Image scanners enable developers to digitize hard copies of pictures and photographs ready for editing and inclusion in multimedia projects. Standard flatbed scanners are available in up to A3 size and scan up to 2400 dots per inch (dpi) with a colour depth of up to 48 bits per pixel.
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