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All rocks - sedimentary, igneous and metamorphic, all pass through a stage in which they change their composition. However, in this process these rocks do not reach extinction but rather cycle from igneous to metamorphic to sedimentary to sediments, and so on. This is known as the rock cycle.
Magma is usually the start of this cycle. Igneous rock is formed when hot, melted magma rises from the earth's inner layers. This magma cools down once it nears the earth's crust. Heat and pressure when put on a igneous will result a transformation to a metamorphic rock. Melting of either igneous or metamorphic rocks will turn it back to magma. Weathering and erosion of either igneous or metamorphic rocks will result into sediments. These sediments when compressed form sedimentary rocks. Like igneous and metamorphic rock, erosion will result to sediments and melting into magma. Heat and pressure of the sedimentary rock will result into a metamorphic rock.
Many a times, transformations are interrupted. Below is an example, in which a igneous rock was interrupted before it completely transformed into a metamorphic rock. Notice the swirls in the rock. Those are parts of igneous rocks in a metamorphic rock
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