What is magma before it reaches the earth's surface?

Magma is the molten rock that is generated beneath the Earth's surface. It becomes lava only after it erupts onto the surface. The term "almost lava" accurately captures the state of magma before it reaches the surface, as it's essentially in the same composition and state as lava, but it has not yet undergone the exposure to atmospheric conditions or volcanic activity that characterizes lava.

Understanding this distinction is important in geological processes, as the behavior and properties of magma can differ from those of lava once it surfaces. For example, the cooling rate, gas content, and crystalline structure can all change dramatically once magma erupts and becomes lava.