object linking and embedding (OLE) A tool used for joining documents in different applications. Changes in either document are reflected in the other document.
object-oriented database The newest type of database structure, well suited for multimedia applications, in which the result of a retrieval operation is an object of some kind, such as a document. Within this object are miniprograms that enable the object to perform tasks, such as displaying a graphic. Object-oriented databases can incorporate sound, video, text, and graphics into a single database record.
object-oriented programming (OOP) A programming technique that creates generic building blocks of a program (the objects). The user then assembles different sets of objects as needed to solve specific problems.
odd parity An error-checking protocol in which the parity bit is set to 1 if the number of 1 digits in a byte adds up to an even number.
on-demand television A British system, serving as a prototype in the U.S., that merges cable television and telephone service to enable subscribers to call into a computer database and order movies or shows "on demand." See also interactive television.
online information service A for-profit firm that makes current news, stock quotes, and other information available to its subscribers over standard telephone lines.
online processing Processing performed while directly connected and accessible to a computer.
open bus system A bus system that has expansion slots on the motherboard.
operating mode The current status of a program, usually displayed by a mode indicator at the bottom of the screen. Common modes are Ready and Wait.
operating system A group of programs that help the computer's components function together smoothly.
optical character recognition (OCR) Recognition of a specific typeface developed to be read by early scanners. OCR devices scan written or typed text and transform it into computer-readable form.
optical disk A large-capacity data storage medium for computers, on which information is stored at extremely high density in the form of tiny pits.
optical mark reader (OMR) A reader that senses magnetized marks made by the magnetic particles in lead from a pencil.
optical processors Experimental processors that use light rather than electrons and are several hundred times faster than the electronic circuits used today.
optical recognition system A scanning device that provides another means of minimizing keyed input by capturing data at the source.
optical scanner A scanning device that captures typed documents, pictures, graphics, or even handwriting for use by a computer.
output The results of processing information shown on a monitor or printer.
output file A file that results from data processing.