An order book is an electronic list of buy and sell orders for a specific stock. An order book lists the number of shares being bid or offered at each price.
A limit order is an order to buy or sell the stock at a specific price. However, there is no guarantee the order will execute as the limit price might be too high or too low.
A market order is an order to buy or sell a stock immediately. This type of order guarantees that the order will be executed but however it does not guarantee the price at which the order will be executed. A market order generally will execute at the current bid (for a sell order) or ask (for a buy order) price.
A stop-loss sell order is an order to sell the stock when it reaches a certain price. Stop-loss orders are designed to limit an investor's loss on a stock.