Here's a breakdown:

* Topsoil is the fertile layer of soil that supports plant life. It's rich in organic matter (decomposed plant and animal material), minerals, and microorganisms.

* Subsoil lies beneath topsoil and is typically less fertile. It contains more clay and less organic matter.

* Parent material is the underlying rock or mineral layer that breaks down over time to form soil.

So, topsoil is the top layer of dirt, where life thrives!