A Stop loss (SL) is the most used (and quite simple) "safeguard", to limiting your potential trading losses. If the market trend runs against your trade/position, the SL will close your open position, activating at the defined SL level.
A Take profit (TP) is the opposite: it will close your open position at a level you define, to save already reached, but so far floating profits.
Take profit and Stop loss levels can be placed in prices or numbers of pips from the price specified in the order, depending on the platform settings.
In Forex trading, Take profits and Stop losses are primarily risk management techniques. You may read our article to understand better.