Here's a breakdown:

* Metamorphic rocks are formed when existing rocks (igneous, sedimentary, or even other metamorphic rocks) are transformed by heat and pressure. This process doesn't melt the rock completely, but it does cause changes in its mineral composition, texture, and structure.

* Heat can come from sources like magma intrusions or tectonic plate movement.

* Pressure is often caused by the weight of overlying rock layers or tectonic forces.

Here are some examples of metamorphic rocks:

* Marble (formed from limestone)

* Slate (formed from shale)

* Gneiss (formed from granite)

* Quartzite (formed from sandstone)

Let me know if you'd like to know more about metamorphic rocks!