frictions

[Luis Fok]

The term friction refers to the resistance that is experienced between two objects as they move relative to each other. This resistance is caused by the interaction of their surfaces, and it is dependent on the properties of both objects, such as their shape and surface roughness.
Friction can be seen in everyday situations, such as when riding a bike or playing with blocks, and it is also a key concept in physics. It plays an important role in many fields, including engineering and physics.