Definition of 'Extended Trading'
Trading conducted on electronic exchanges either after regular trading hours are over or before they begin. Usually such trading is limited in its volume compared to regular trading hours. Pre-market trading in the U.S. markets usually runs between 8am and 9:30am EST, and after-market trading typically runs from 4pm until 6:30pm EST.
Investopedia explains 'Extended Trading'
Extended trading volumes have risen markedly over the past decade as more investors become comfortable with the technology platforms and financial markets become increasingly global.
The rise of electronic communications networks (ECN) have democratized extended-hours trading, allowing even small retail investors the chance to place trades during periods of time once reserved for large institutional investors.