A market order is an order to open a buy or sell position at the best current available price.
A pending order is an order to buy or sell an instrument at a specified future price, only if the market reaches that specific price.
A limit order is triggered when the market moves past your specified entry level, providing the limit order price or a better price on your trade entry – but never a worse price.
A stop loss is a conditional order set at a fixed price level which is aimed at closing a position after a certain price has been reached. A stop is triggered when the market moves in an unfavorable direction for the trader. It is designed to prevent further losses when a position is losing money.
A trailing stop is a type of stop-loss order that moves with the trade as the market price fluctuates. It does not remain at a fixed price and is therefore set in a distance of pips. The trailing stop only activates when the trailing stop level has been reached. It is designed to realize the profit made by the position.