I had to look it up, but Plus500 is a new UK-based online trading company, not familiar to those in the USA (where you posted). Trying to trade on an android app?
Stock index futures trade almost 24 hrs a day during the week. The /ym, /es, /nq, /tf are all popular index futures. These are the Dow futures, emini S&P, Nasdaq and Russell futures, respectively.
The cash indices like the DJIA and S&P 500 and Nasdaq do not change when floor trading is closed.
Individual stocks trade in extended hours after the market closes and in pre-market trading.
"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. "
http://www.investopedia.com/terms/e/exte...
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.
Typical after-hours trading sessions run from 4pml 6:30pm Eastern Standard Time for the Nasdaq 100.
Lower liquidity and wider bid-ask spreads are a common feature of after-hours trading. After-hours trading is heaviest in the first hour or two after markets close, before tapering off sharply.
Definition of 'After-Hours Trading - AHT'
Trading after regular trading hours on the major exchanges.
http://www.investopedia.com/terms/a/afte...
When all constituents of an index are not trading, shouldn't the price of an index remain constant?
