Over 700 finance terms, Shmooped to perfection.
When the world was older and slower, trading during "normal hours" went from 9:30 until 4:00 New York time. Today, the world's markets drink lots of Red Bull. "Extended hours" means in theory 24/7. In practice, most after-hours trading dries up around 8PM and most pre-market trading begins around 5:30 A.M. Money never sleeps.