Market, limit, and stop orders are the three most commonly used order types.Each of them has its own distinctive features.
A market order is an order to buy or sell a stock at the best available price. It has the best chance of filling, but the filling price is not certain. A limit order is an order to trade a security at a specified price or better. It guarantees the filling price, but it is not guaranteed to be filled. A stop order, also called a stop-loss order, is an order to trade a security when it has reached above or below a specified price. It is triggered at the stop price and filled as a market order.

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