1. Igneous rocks: These rocks are formed when magma or lava cools and solidifies. Magma is molten rock that is found beneath the Earth's surface, while lava is molten rock that has erupted onto the Earth's surface. Igneous rocks can be either intrusive or extrusive. Intrusive igneous rocks are formed when magma cools and solidifies beneath the Earth's surface, while extrusive igneous rocks are formed when lava cools and solidifies on the Earth's surface.

2. Sedimentary rocks: These rocks are formed when sediments, such as sand, mud, and gravel, are compacted and cemented together. Sedimentary rocks can be either clastic or chemical. Clastic sedimentary rocks are formed when sediments are compacted and cemented together, while chemical sedimentary rocks are formed when minerals precipitate out of water.

3. Metamorphic rocks: These rocks are formed when existing rocks are changed by heat, pressure, or chemical reactions. Metamorphic rocks can be either foliated or non-foliated. Foliated metamorphic rocks have a layered or banded appearance, while non-foliated metamorphic rocks do not have a layered or banded appearance.