Understanding friction on horizontal and inclined planes involves grasping the concepts of the coefficient of friction (μ) and the forces acting on objects. On a horizontal plane, friction is calculated using the normal force and the coefficient of friction, while on inclined planes, the angle of inclination affects the normal force and, consequently, the frictional force. Key factors include the weight of the object, the angle of the incline, and the surface materials. Resources such as physics textbooks, online tutorials, and educational videos can provide clearer explanations and examples. Mastering these principles will enhance comprehension of friction in various scenarios.