What is true about frictional forces?

Frictional forces are fundamental in physics, and their primary characteristic is that they always oppose the motion of an object. This opposition arises because friction acts in the opposite direction to the movement or potential movement of an object. When an object is in motion or is about to move, friction works to resist this change, which is crucial for various everyday applications, such as stopping a car or allowing people to walk without slipping.

This opposing nature of friction is why most objects need a certain amount of force to overcome friction to start moving or to maintain their motion. Without friction, objects would slide indefinitely in the absence of other forces, making control over movement significantly difficult. Understanding this concept is vital in both practical applications (like engineering and safety) and theoretical studies in physics.