| S. No. |
Forward Chaining |
Backward Chaining |
| 1. |
Forward chaining starts from known facts and applies inference rule to extract more data unit it reaches to the goal. |
Backward chaining starts from the goal and works backward through inference rules to find the required facts that support the goal. |
| 2. |
It is a bottom-up approach |
It is a top-down approach |
| 3. |
Forward chaining is known as data-driven inference technique as we reach to the goal using the available data. |
Backward chaining is known as goal-driven technique as we start from the goal and divide into sub-goal to extract the facts. |
| 4. |
Forward chaining reasoning applies a breadth-first search strategy. |
Backward chaining reasoning applies a depth-first search strategy. |
| 5. |
Forward chaining tests for all the available rules |
Backward chaining only tests for few required rules. |
| 6. |
Forward chaining is suitable for the planning, monitoring, control, and interpretation application. |
Backward chaining is suitable for diagnostic, prescription, and debugging application. |
| 7. |
Forward chaining can generate an infinite number of possible conclusions. |
Backward chaining generates a finite number of possible conclusions. |
| 8. |
It operates in the forward direction. |
It operates in the backward direction. |
| 9. |
Forward chaining is aimed for any conclusion. |
Backward chaining is only aimed for the required data. |