1. A technical practice in which two programmers work together at one workstation (one screen, keyboard, and mouse among the pair). One person, the driver, writes code while the other person, the observer or navigator, reviews each line of code as it is typed in. The two programmers switch roles frequently. (based on Wikipedia) 2. One of the original 12 extreme programming practices. 3. A technique that allows for very rapid feedback of code as it is being created. See also technical practices.