The most important Sessions on Forex are:
The Asian Session (7pm – 4am EST) – During this period, you can successfully day trade especially if you trade the yen. USD/JPY is a good choice if you plan to trade on this session. This period is not as volatile as the US session or the European session, but it’s possible to trade it and achieve a good performance;
The European Session (2am – 12pm EST) – This is one of the best periods to trade Forex. Since most of the dealing desks of large banks are located in London, the majority of major Forex transactions are completed during this session. During this period you can implement a successfully strategy on any currency pair.
The U.S. Session (8am – 5pm EST) – This is another great period to implement your forex strategies. Volatility is good, and you can expect good volatility on any currency pair.
http://telugucruut.blogspot.com/2011/07/subbulu-kamam.html