In what conditions we use forward and backwardchaining in prolog specify?

Explanation:

Forward Chaining:

As the name suggests, Forward Chaining is the method of arriving at the goal with the available data and the data that is produced from the available data. With the help of the available data more data is produced by using inference rules. With the combination of available data and the produced data, a goal will be reached.

Backward Chaining:

As the name suggests, Backward Chaining is the method of finding the reasons behind the goal or hypothesis. It is used when the goal is present and checking if the available data supports / satisfies the goal.