The decomposition of rock from exposure to water and atmospheric gases is known as weathering.

There are two main types of weathering:

* Physical weathering: This involves the breakdown of rocks into smaller pieces without changing their chemical composition. Examples include freeze-thaw cycles, abrasion, and pressure release.

* Chemical weathering: This involves the breakdown of rocks through chemical reactions. Examples include oxidation, hydrolysis, and carbonation.

Water and atmospheric gases like oxygen and carbon dioxide play significant roles in both physical and chemical weathering.