you’re questions is very generalised so i’ll give two answers
1) Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. Once a rock has been broken down, a process called erosion transports the bits of rock and mineral away.
2) When rocks break in response to stress, the resulting break is called a fracture. If rocks on one side of the break shift relative to rocks on the other side, then the fracture is a fault.