This document discusses weathering and erosion. It defines weathering as the breakdown of rocks at Earth's surface through physical or chemical processes. Erosion is defined as the physical transportation of weathered material by forces like water, wind, ice or gravity. It then describes the three main types of weathering: mechanical (or physical) weathering which breaks rocks without changing their chemical composition, chemical weathering which decomposes rocks through chemical reactions, and biological weathering caused by organisms. Specific examples of each type of weathering like frost wedging, hydration and burrowing are provided. Factors that influence the rate of weathering like climate, mineral composition and slope are also outlined.