It's important to understand that the difference between lava and magma isn't about how the igneous rocks form, but rather where the molten rock is located:

* Magma: Molten rock found beneath the Earth's surface.

* Lava: Molten rock that has erupted onto the Earth's surface.

Here's how igneous rocks form from both:

Igneous Rocks from Cooling Magma:

1. Intrusive Igneous Rocks: Magma cools and solidifies underground, forming intrusive igneous rocks. These rocks cool slowly, allowing for larger crystals to form. Examples include granite, gabbro, and diorite.

2. Extrusive Igneous Rocks: Magma sometimes rises to the surface as lava. When it erupts and cools, it forms extrusive igneous rocks. Because the cooling process is much faster, the crystals tend to be smaller. Examples include basalt, rhyolite, and andesite.

Key Differences:

* Location: Magma is underground, while lava is above ground.

* Cooling Rate: Magma cools more slowly than lava, leading to larger crystals in intrusive rocks.

* Texture: Intrusive igneous rocks often have a coarse-grained texture (visible crystals), while extrusive rocks can be fine-grained or glassy.

In summary:

Igneous rocks form from the cooling and solidification of both magma and lava. The location of the molten rock (underground vs. above ground) influences the cooling rate and the final texture of the rock.