I am thinking of dabbling in stocks, primarily trade forex. Was backtesting some ideas using OHLC data from finance.google.com. I have a basic question. Is is possible to buy/sell at the open price and buy/sell at the close price. Or these open and close prices as reported on google finance are some kind of average prices (average from auctions ??) - and its not possible to buy/sell at them. I am doubtful because I have read on this board that many morning open orders don't get filled (like bright trading opening only strategy etc.). Also, there is a MOC type of order (market on close). It will be great if someone can explain how this kind of order works ? Is it guaranteed that this order will fill you at closing price ? Thanks in advance.