Order Types traders use:

1. Market Order - an order to buy or sell a stock at the best bid or asks price. A market order will get filled for you fast, but you might not like the price! By then you have no choice but to take the price and hope your day trade is heading in the right direction. If the market is moving fast and you simply have to get in, sometimes a market order is the only way.
2. 
   Limit Order - an order to buy or sell a stock at a specified price or better. This is the day trading order of choice for day traders and indeed traders of other types..
3. 
   Stop Order - an order that becomes a market order when a specified price is reached. This order mostly use to protect a day trading position from incurring larger than acceptable losses . A "buy stop" order is placed above the current price and a "sell stop" order is placed below the current price.