Input and Output

Input
Input is any data and instructions entered into the memory of a computer. People have a variety of options for entering input into a computer. Data is a collection of unprocessed text, numbers, images, audio and video. Once data is in memory, the computer interprets and executes instructions to process the data into information. Instructions entered into the computer can be in the form of programs, commands and user responds.
An input device is any hardware component that allows users to enter data and instructions into a computer. Depending on the application and your particular requirement, the input device selected may vary.
The following are the examples of some of the input
1. Keyboard and pointing devices
2. Gaming and media player controllers
3. Voice Input
4. Input for PDAs, Smart Phones and Tablet PCs
5. Video Input

Output
Output is data that has been processed into a useful form. That is, computers process data (input) into information (output). A computer generates several types of output, depending on the hardware and software being used and the requirements of the user.
Users view or watch output on a screen, print it or hear it through speakers, headphones, or earphones. Monitors, notebook computers, Tablet PCs, portable media players, PDAs, and smart phones have screens that allow users to view documents, Web sites, e-mail messages, pictures, videos, movies and other types of output. Some printers produce black-and-white documents and others produce brilliant colors, enabling users to print color documents, photographs and transparencies. Through the computer’s speakers, headphones or earphones, users listen to sounds, music, and voice messages.
While working with a computer, a user encounters four basic categories of output: text, graphics, audio and video. Very often, a single form of output, such as Web page, includes more than one of these catrgories.