There are two main types of weathering: mechanical and chemical. Mechanical weathering breaks rocks into smaller pieces through processes like frost wedging, unloading, and biological activity. Chemical weathering transforms rocks into new compounds through reactions with water and acids. Water is the most important agent of chemical weathering, as it dissolves oxygen and carbon dioxide to form acids. These acids then react with minerals like feldspar and limestone. The rate of weathering depends on factors like climate, rock characteristics, and mechanical breakdown.