What type of rock is formed from the cooling of molten rock either at or below the Earth's surface?

Igneous rock is formed when molten rock, known as magma when it is beneath the Earth's surface and lava when it is above the surface, cools and solidifies. This process can occur either underground, where the cooling happens slowly, leading to the formation of large crystals, or at the surface, where it cools rapidly, producing small crystals or a glassy texture.

Igneous rocks are categorized into two main types based on where they are formed: intrusive (or plutonic) igneous rocks, which form from cooling magma below the Earth's surface, and extrusive (or volcanic) igneous rocks, which form from lava that cools on the surface. Common examples of intrusive igneous rock include granite, while basalt is a common example of extrusive igneous rock, though basalt is more specifically defined as a type of igneous rock that forms from the rapid cooling of lava.

Metamorphic rock, on the other hand, is not formed from molten material but rather from the transformation of existing rock types through heat, pressure, or chemically active fluids. Sedimentary rock is formed from the accumulation of sediment, which can come from the erosion of other rocks, biological activity, or precipitation from solution.