Rock type is a classification system used in geology to categorize and identify different types of rocks based on their mineral composition, texture, and formation process. There are three main categories of rock types: igneous, sedimentary, and metamorphic. Igneous rocks are formed from the solidification of molten magma or lava and can be further classified into intrusive (formed underground) and extrusive (formed on the surface). Sedimentary rocks are formed from the accumulation and compression of sediment particles, such as sand, mud, and organic material, over time. They are typically found in layers or strata. Metamorphic rocks are formed from the alteration of existing rocks due to high temperature, pressure, or chemical processes. This can result in the transformation of original rock types into new mineral compositions and textures. Each rock type has unique characteristics that can provide valuable information about the Earth's geological history and processes. Studying rock types can help geologists understand the formation of the Earth's crust, environmental conditions, and geological events that have shaped the planet over millions of years.