Intrusive rocks are formed when magma cools and solidifies beneath the surface of the Earth. They are typically coarse-grained and have a crystalline texture. Some common examples of intrusive rocks include granite, diorite, and gabbro.

Extrusive rocks are formed when magma cools and solidifies on the surface of the Earth. They are typically fine-grained and have a glassy texture. Some common examples of extrusive rocks include basalt, rhyolite, and andesite.

The main difference between intrusive and extrusive rocks is their texture. Intrusive rocks have a crystalline texture because the magma has had time to cool and crystallize slowly beneath the surface of the Earth. Extrusive rocks have a glassy texture because the magma has cooled quickly on the surface of the Earth.

Here is a table summarizing the key differences between intrusive and extrusive rocks:

| Characteristic | Intrusive Rocks | Extrusive Rocks |

|---|---|---|

| Texture | Coarse-grained, crystalline | Fine-grained, glassy |

| Cooling rate | Slow | Fast |

| Location | Beneath the surface of the Earth | On the surface of the Earth |

| Examples | Granite, diorite, gabbro | Basalt, rhyolite, andesite |

I hope this helps!